e2e: enhance SIGDescribe

framework.SIGDescribe is better because:
- Ginkgo uses the source code location of the test, not of the wrapper,
  when reporting progress.
- Additional annotations can be passed.

To make this a drop-in replacement, framework.SIGDescribe generates a function
that can be used instead of the former SIGDescribe functions.

windows.SIGDescribe contained some additional code to ensure that tests are
skipped when not running with a suitable node OS. This gets moved into a
separate wrapper generator, to allow using framework.SIGDescribe as intended.
To ensure that all callers were modified, the windows.sigDescribe isn't
exported anymore (wasn't necessary in the first place!).

test/e2e/cloud/gcp/auth/framework.go

@@ -16,9 +16,7 @@ limitations under the License.
 
 package auth
 
-import "github.com/onsi/ginkgo/v2"
+import "k8s.io/kubernetes/test/e2e/framework"
 
 // SIGDescribe annotates the test with the SIG label.
-func SIGDescribe(text string, body func()) bool {
-	return ginkgo.Describe("[sig-auth] "+text, body)
-}
+var SIGDescribe = framework.SIGDescribe("auth")