Increase number of iterations in TestDefaulting

Fixes #39180

pkg/api/defaulting_test.go

@@ -149,7 +149,7 @@ func TestDefaulting(t *testing.T) {
 				if !expectedChanged || changedOnce {
 					break
 				}
-				if iter > 200 {
+				if iter > 300 {
 					t.Errorf("expected %s to trigger defaulting due to fuzzing", gvk)
 					break
 				}