⚠️ remove DNS type from v1alpha4

[ludusrusso]

What this PR does / why we need it:

This PR removes the DNS.Type field from v1alpha4, as discussed in #4177

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 #4177

/cc @fabriziopandini

[k8s-ci-robot]

Hi @ludusrusso. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[fabriziopandini]

/ok-to-test

[fabriziopandini]

First pass, I still have some files to check, but I plan to make another round of comments as soon as CI is passing.
@ludusrusso if I get the CI error right, you have to run make-generate to get the updated conversion files; if the system can't generate some conversion files due to the changes, you have to provide the missing conversion files in the conversion.go files like in https://github.com/fabriziopandini/cluster-api/blob/404215420c883e8003fb9422cd81a46eb2b678a2/bootstrap/kubeadm/api/v1alpha3/conversion.go#L73-L77

[ludusrusso]

@ludusrusso: The following tests failed, say /retest to rerun all failed tests:

Test name Commit Details Rerun command
pull-cluster-api-apidiff-main ca725f2 link /test pull-cluster-api-apidiff-main
pull-cluster-api-test-main ca725f2 link /test pull-cluster-api-test-main
pull-cluster-api-verify ca725f2 link /test pull-cluster-api-verify
Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

Uhm, it seems I forgot to run tests locally after my last push 😇

[ludusrusso]

First pass, I still have some files to check, but I plan to make another round of comments as soon as CI is passing.
@ludusrusso if I get the CI error right, you have to run make-generate to get the updated conversion files; if the system can't generate some conversion files due to the changes, you have to provide the missing conversion files in the conversion.go files like in https://github.com/fabriziopandini/cluster-api/blob/404215420c883e8003fb9422cd81a46eb2b678a2/bootstrap/kubeadm/api/v1alpha3/conversion.go#L73-L77

Got it! I'm working to fix this!

[ludusrusso]

@fabriziopandini Ok, I think now this PR is ok! What do you think?

Test pull-cluster-api-apidiff-mai is still failing but I think this is normal, am I right?

[fabriziopandini]

@ludusrusso the PR looks great now! I have only a couple of nits about comments, to keep track of why custom conversion functions are required.

pull-cluster-api-apidiff-main is just a signal for the reviewer that the PR Is introducing API changes, but this is expected in this case and properly reported via the ⚠️ in the title

[fabriziopandini]

/lgtm

@vincepri @sbueringer PTAL

[sbueringer]

It looks good to me, but definitely not familiar enough with the details of our conversion..

[k8s-ci-robot]

@ludusrusso: The following test failed, say /retest to rerun all failed tests:

Test name	Commit	Details	Rerun command
pull-cluster-api-apidiff-main	a0186d2	link	/test pull-cluster-api-apidiff-main

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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. I understand the commands that are listed here.

[fabriziopandini]

/lgtm

[CecileRobertMichon]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: CecileRobertMichon

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