https://github.com/kubernetes/kubernetes/pull/109728 added a
golangci-strict.yaml where gingkolinter and stylecheck (some recent additions
to golangci.yaml) were missing.
To prevent such mistakes in the future, lines that are intentionally different
get annotated with a comment about golangci-strict.yaml or golangci.yaml.
Then a suitable diff command in the new verify-golangci-lint-config.sh checks
that only such lines, comments and blank lines are different.
It is useful to check new code with a stricter configuration because we want it
to be of higher quality. Code reviews also become easier when reviewers don't
need to point out inefficient code manually.
What exactly should be enabled is up for debate. The current config uses the
golangci-lint defaults plus everything that is enabled explicitly by the normal
golangci.yaml, just to be on the safe side.
