fix: crd proxy path

[dantli]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespace from that line:

/kind api-change
/kind bug
/kind cleanup
/kind deprecation
/kind design
/kind documentation
/kind failing-test
/kind feature
/kind flake

What this PR does / why we need it:
CustomResourceHandler user r.RequestURI as Path. It will get 404 response when RequestURI has params, like /api/v1/namespaces?limit=500. The correct Path is /api/v1/namespaces, not /api/v1/namespaces?limit=500

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.: