Drop release-0.3 from book docs

[Prajyot-Parab]

What this PR does / why we need it:

• Drop release-0.3 from book docs

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:

/area provider/ibmcloud

1. Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

Release note:

Drop release-0.3 from book docs

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[Prajyot-Parab]

/cherrypick release-0.5

[k8s-infra-cherrypick-robot]

@Prajyot-Parab: once the present PR merges, I will cherry-pick it on top of release-0.5 in a new PR and assign it to you.

In response to this:

/cherrypick release-0.5

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.

[Prajyot-Parab]

/cherrypick release-0.4

[k8s-infra-cherrypick-robot]

@Prajyot-Parab: once the present PR merges, I will cherry-pick it on top of release-0.4 in a new PR and assign it to you.

In response to this:

/cherrypick release-0.4

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.

[mkumatag]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mkumatag, Prajyot-Parab

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• OWNERS [mkumatag]

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[k8s-infra-cherrypick-robot]

@Prajyot-Parab: new pull request created: #1373

In response to this:

/cherrypick release-0.5

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]

@Prajyot-Parab: new pull request created: #1374

In response to this:

/cherrypick release-0.4

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.