Permissions bugfix and tests

• Unit tests, added to CI
• Permissions bugfix with nested fields

This is dependent on the MR: djangoldp!130 (merged)

When this is merged we can re-run the pipeline and the failing test should pass

added 1 commit

• ded087aa - bugfix: added image to gitlab-ci.yml

Compare with previous version

changed the description

mentioned in issue djangoldp#244 (closed)

merged

mentioned in commit 4b533ae3