Remove unused function setCredentials

[willie-yao]

What type of PR is this?
/kind cleanup

What this PR does / why we need it:
setCredentials is unused since identityRef is now required as of #4201

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

• cherry-pick candidate

TODOs:

• squashed commits
• includes documentation
• adds unit tests

Release note:

NONE

[willie-yao]

/cherry-pick release-1.11

[k8s-infra-cherrypick-robot]

@willie-yao: once the present PR merges, I will cherry-pick it on top of release-1.11 in a new PR and assign it to you.

In response to this:

/cherry-pick release-1.11

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[CecileRobertMichon]

@willie-yao unit tests are failing PTAL

[willie-yao]

@CecileRobertMichon Turns out a ton of unit tests need to be refactored (basically all the controller tests) due to them needing to expect AzureClusterIdentity for all cases, so it may take me a bit to get all that done. Will mark the PR as WIP

[mboersma]

/lgtm
/assign @nojnhuh

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: b36e104be79eefc94d5a5c0a7b755bde9e6c6bb0

[mboersma]

/hold
for squash

[nojnhuh]

/lgtm
/approve

@willie-yao Could you please open an issue describing any follow-up refactoring for tests?

[willie-yao]

/hold cancel

[nojnhuh]

@willie-yao Was the dependabot PR in the commit history here intentional?

[willie-yao]

@willie-yao Was the dependabot PR in the commit history here intentional?

Whoops lemme fix that

[nojnhuh]

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 1c5c487388fa39620f76737c1c794c5a55660011

[mboersma]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mboersma, nojnhuh

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [mboersma,nojnhuh]

Approvers can indicate their approval by writing /approve in a comment
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[k8s-infra-cherrypick-robot]

@willie-yao: #4208 failed to apply on top of branch "release-1.11":

Applying: Remove unused function setCredentials
Using index info to reconstruct a base tree...
M	azure/scope/clients_test.go
M	azure/scope/cluster.go
M	azure/scope/cluster_test.go
M	azure/scope/managedcontrolplane.go
M	azure/scope/managedcontrolplane_test.go
M	controllers/azurecluster_controller_test.go
M	controllers/azurejson_machine_controller_test.go
M	controllers/azurejson_machinepool_controller_test.go
M	controllers/azurejson_machinetemplate_controller_test.go
M	controllers/azuremachine_controller_test.go
M	controllers/azuremanagedcontrolplane_controller_test.go
M	controllers/azuremanagedmachinepool_controller_test.go
M	controllers/helpers_test.go
M	exp/controllers/azuremachinepool_controller_test.go
M	exp/controllers/azuremachinepoolmachine_controller_test.go
Falling back to patching base and 3-way merge...
Auto-merging exp/controllers/azuremachinepoolmachine_controller_test.go
CONFLICT (content): Merge conflict in exp/controllers/azuremachinepoolmachine_controller_test.go
Auto-merging exp/controllers/azuremachinepool_controller_test.go
Auto-merging controllers/helpers_test.go
CONFLICT (content): Merge conflict in controllers/helpers_test.go
Auto-merging controllers/azuremanagedmachinepool_controller_test.go
Auto-merging controllers/azuremanagedcontrolplane_controller_test.go
CONFLICT (content): Merge conflict in controllers/azuremanagedcontrolplane_controller_test.go
Auto-merging controllers/azuremachine_controller_test.go
CONFLICT (content): Merge conflict in controllers/azuremachine_controller_test.go
Auto-merging controllers/azurejson_machinetemplate_controller_test.go
Auto-merging controllers/azurejson_machinepool_controller_test.go
CONFLICT (content): Merge conflict in controllers/azurejson_machinepool_controller_test.go
Auto-merging controllers/azurejson_machine_controller_test.go
Auto-merging controllers/azurecluster_controller_test.go
CONFLICT (content): Merge conflict in controllers/azurecluster_controller_test.go
Auto-merging azure/scope/managedcontrolplane_test.go
CONFLICT (content): Merge conflict in azure/scope/managedcontrolplane_test.go
Auto-merging azure/scope/managedcontrolplane.go
Auto-merging azure/scope/cluster_test.go
CONFLICT (content): Merge conflict in azure/scope/cluster_test.go
Auto-merging azure/scope/cluster.go
CONFLICT (modify/delete): azure/scope/clients_test.go deleted in Remove unused function setCredentials and modified in HEAD. Version HEAD of azure/scope/clients_test.go left in tree.
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 Remove unused function setCredentials
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

In response to this:

/cherry-pick release-1.11

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[k8s-infra-cherrypick-robot]

@willie-yao: #4208 failed to apply on top of branch "release-1.12":

Applying: Remove unused function setCredentials
Using index info to reconstruct a base tree...
M	azure/scope/cluster.go
M	azure/scope/cluster_test.go
M	azure/scope/managedcontrolplane.go
M	azure/scope/managedcontrolplane_test.go
M	controllers/azurecluster_controller_test.go
M	controllers/azurejson_machine_controller_test.go
M	controllers/azurejson_machinepool_controller_test.go
M	controllers/azuremanagedcontrolplane_controller_test.go
M	controllers/helpers_test.go
Falling back to patching base and 3-way merge...
Auto-merging controllers/helpers_test.go
Auto-merging controllers/azuremanagedcontrolplane_controller_test.go
CONFLICT (content): Merge conflict in controllers/azuremanagedcontrolplane_controller_test.go
Auto-merging controllers/azurejson_machinepool_controller_test.go
CONFLICT (content): Merge conflict in controllers/azurejson_machinepool_controller_test.go
Auto-merging controllers/azurejson_machine_controller_test.go
Auto-merging controllers/azurecluster_controller_test.go
Auto-merging azure/scope/managedcontrolplane_test.go
CONFLICT (content): Merge conflict in azure/scope/managedcontrolplane_test.go
Auto-merging azure/scope/managedcontrolplane.go
Auto-merging azure/scope/cluster_test.go
Auto-merging azure/scope/cluster.go
Removing azure/scope/clients_test.go
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 Remove unused function setCredentials
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

In response to this:

/cherry-pick release-1.12

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[willie-yao]

Note: I'm holding off on making a cherry-pick to 1.11 for now since the ClusterClass for Managed Clusters PR was not merged for that release which causes massive merge conflicts. @CecileRobertMichon Would we want to do this cherry-pick even though there isn't a functional difference?

[CecileRobertMichon]

If this is just a cleanup (no bug fix) + refactor then we don't believe we want to cherry-pick this (even in 1.12)