remove manual edit strings from crd manifests

[Huang-Wei]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

With this PR, CRDs hosted in this repo or referenced in externals repos are recommended to add:

// +kubebuilder:metadata:annotations="api-approved.kubernetes.io=https://github.com/kubernetes-sigs/scheduler-plugins/pull/XYZ"

to their types.go, but not mandatory.

hack/verify-crdgen.sh is able to catch any inconsistency between types.go and CRD manifests.

Which issue(s) this PR fixes:

A follow-up of #479.

Special notes for your reviewer:

Does this PR introduce a user-facing change?

+kubebuilder:metadata:annotations is recommended but no longer mandatory to be defined in CRD types.go

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[Huang-Wei]

@lianghao208 could you please help review?

[lianghao208]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Huang-Wei, lianghao208

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