Merge branch 'django4' into 'master'

.gitlab-ci.yml

djangoldp_circle/admin.py

djangoldp_circle/apps.py

djangoldp_circle/djangoldp_urls.py

...s/0035_alter_circle_options_alter_circlemember_options.py

djangoldp_circle/models.py

djangoldp_circle/serializers.py

djangoldp_circle/tests/runner.py

djangoldp_circle/tests/tests_view.py

djangoldp_circle/xmpp.py

setup.cfg