Add subresource support to kubectl

[nikhita]

Enhancement Description

• One-line enhancement description (can be used as a release note): Add a new flag --subresource to kubectl commands like get, patch, edit and replace commands to allow fetching and updating subresources like status, scale, etc.

• Kubernetes Enhancement Proposal: https://github.com/kubernetes/enhancements/tree/master/keps/sig-cli/2590-kubectl-subresource

• Discussion Link:

  • Discussion in the POC PR - https://github.com/kubernetes/kubernetes/pull/99556
  • mailing list/meeting link: https://youtu.be/zUa7dudYCQM?t=299

• Primary contact (assignee): @nikhita @MadhavJivrajani

• Responsible SIGs: SIG CLI

• Enhancement target (which target equals to which milestone):

  • Alpha release target (x.y): v1.24
  • Beta release target (x.y): v1.27
  • Stable release target (x.y): v1.31

• [x] Alpha

  • [x] KEP (k/enhancements) update PR(s):
  • https://github.com/kubernetes/enhancements/pull/2600
  • [x] Code (k/k) update PR(s):
  • apiserver changes - https://github.com/kubernetes/kubernetes/pull/103516
  • kubectl changes - https://github.com/kubernetes/kubernetes/pull/99556
  • [x] Docs (k/website) update PR(s):
  • https://github.com/kubernetes/website/pull/32604

• [x] Beta

  • [x] KEP (k/enhancements) update PR(s):
  • https://github.com/kubernetes/enhancements/pull/3729
  • [x] Code (k/k) update PR(s):
  • https://github.com/kubernetes/kubernetes/pull/116595
  • https://github.com/kubernetes/kubernetes/pull/116590
  • https://github.com/kubernetes/kubernetes/pull/116619
  • [x] Docs (k/website) update(s):
  • https://github.com/kubernetes/website/pull/39828

• [ ] Stable

  • [x] KEP (k/enhancements) update PR(s):
  • https://github.com/kubernetes/enhancements/pull/4468
  • [ ] Code (k/k) update PR(s):
  • TODO
  • [ ] Docs (k/website) update(s):
  • TODO