fix: deprecation assertEquals

djangoldp/tests/tests_auto_author.py

djangoldp/tests/tests_backlinks_service.py

djangoldp/tests/tests_cache.py

djangoldp/tests/tests_get.py

djangoldp/tests/tests_inbox.py

djangoldp/tests/tests_ldp_model.py

djangoldp/tests/tests_model_serializer.py

djangoldp/tests/tests_pagination.py

djangoldp/tests/tests_post.py

djangoldp/tests/tests_update.py