Istio 1.4.0 templated manifest contains creationTimestamp

[Stono]

Bug description
I've noticed in the templated yaml for istio 1.4.0, a bunch of manifests contain a creationTimestamp field, and they probably shouldn't.

Expected behavior
creationTimestamp should be added by the server not part of these manifests

Steps to reproduce the bug
helm template 1.4.0

Version (include the output of istioctl version --remote and kubectl version and helm version if you used Helm)
1.4.0

How was Istio installed?

Environment where bug was observed (cloud vendor, OS, etc)

[jasonwzm]

We use direct transformation from CustomResourceDefinition object to yaml in CRD generation (which is the same approach used in kubebuilder). @Stono did it cause validation error on your side?
Anyhow, I will create a patch for this.