Add Gateway API CRDs to the repo with kustomize

[lucacome]

Proposed changes

Problem: We don't have a way to tie a version of the Gateway API to our release (or edge). There's also not a single source of truth for the API version.

Solution: Use kustomize to add a specific version of the CRDs to our codebase. This way we only have to manage the version in one place and we can tie it to our releases.

Please focus on (optional): Deploying standard and experimental versions of the API or main for our tests.

Continuation of #1803

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.

NONE

[pleshakov]

nice!

[kate-osborn]

This is great!