Use sentry in all environments

It still is optional though

gitlab-ci/test.yml

@@ -9,7 +9,7 @@ python-tests:
     - pip install poetry --quiet
     - poetry config cache-dir .cache/poetry
     - poetry config virtualenvs.in-project true
-    - poetry install --no-interaction --quiet
+    - poetry install --no-interaction --quiet --extras sentry
   script:
     - poetry run coverage run src/manage.py test newsreader
     - poetry run coverage report