Add SupportedFeatures to GatewayClassStatus

[ciarams87]

Proposed changes

Problem: As part of Gateway API release 1.4, the field supportedFeatures in GatewayClass spec is being moved to standard. We don't currently support this.

Solution: Add SupportedFeatures to GatewayClassStatus

Testing: Describe any testing that you did.

Please focus on (optional): If you any specific areas where you would like reviewers to focus their attention or provide
specific feedback, add them here.

Closes #3943

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

Release notes

If this PR introduces a change that affects users and needs to be mentioned in the release notes,
please add a brief note that summarizes the change.

Add SupportedFeatures to GatewayClassStatus

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.13%. Comparing base (a5a0f72) to head (a9caf4f).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4236      +/-   ##
==========================================
+ Coverage   86.10%   86.13%   +0.02%     
==========================================
  Files         131      132       +1     
  Lines       14162    14192      +30     
  Branches       35       35              
==========================================
+ Hits        12194    12224      +30     
  Misses       1765     1765              
  Partials      203      203              

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