Add django-override-storage to test reqs

.gitlab-ci.yml

@@ -25,7 +25,7 @@ pytest:
   stage: test
   before_script:
     - pip install -U pip setuptools
-    - pip install -r test_requirements.txt
+    - pip install -r requirements-test.txt
     - apt-get update && cat system-requirements.txt | xargs apt-get install -y
   script:
     - pytest -v --cov=ojusomap