Fix commented out tests in serializers_regress
|Reported by:||timo||Owned by:||nobody|
|Has patch:||no||Needs documentation:||no|
|Needs tests:||no||Patch needs improvement:||no|
tests/serializers_regress/tests.py contains some commented out items in the test_data list. I think it may be because not all serializers support those items. If this is the case, we should make appropriate modifications so the tests are run where they are supported and skipped where not.