compatibility versions: add linting as beta criteria

As discussed in
kubernetes/kubernetes#125830 (comment),
the stand-alone linter was okay as the initial solution, but integration into
golangci-lint is expected to perform better and thus should be done before
graduation to beta.

Author: pohly

keps/sig-architecture/4330-compatibility-versions/README.md

@@ -881,6 +881,7 @@ We intend to have this up and running for Beta
   (Leveraging work from KEP-4355 if possible)
 - All existing features migrated to versioned feature gate - [kubernetes #125031](https://github.com/kubernetes/kubernetes/issues/125031)
 - Verification machinery added - [kubernetes #125032](https://github.com/kubernetes/kubernetes/issues/125032) 
+- Integrate [test/featuregate_linter](https://github.com/kubernetes/kubernetes/blob/35488ef5c7212a3d491b86e02b1ba05dbbc4b894/test/featuregates_linter/README.md) into golangci-lint
 
 <!--
 **Note:** *Not required until targeted at a release.*