fix: Revert Django 4.0 addition (leave for major bump)

Django 4.0 breaks some of our tests. Dropping support for Python 3.6 and Django 2.2 is also overdue, so we can combine those three in a coming release shortly

.github/workflows/testing.yml

@@ -39,14 +39,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [ "3.6", "3.7", "3.8", "3.9", "3.10" ]
-        django-version: [ "2.2", "3.0", "3.1", "3.2", "4.0" ]
-        exclude:
-          # Django v4 drops Python 3.6/3.7 support
-          - django-version: 4.0
-            python-version: 3.7
-          - django-version: 4.0
-            python-version: 3.6
+        python-version: [ "3.6", "3.7", "3.8" , "3.9", "3.10" ]
+        django-version: [ "2.2", "3.0", "3.1", "3.2" ]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
@@ -56,7 +50,7 @@ jobs:
         id: poetry-cache
         with:
           path: ~/.local
-          key: key-0
+          key: key-1
       - name: Install poetry
         uses: snok/install-poetry@v1
         with:
@@ -66,22 +60,24 @@ jobs:
         id: cache-venv
         with:
           path: .venv
-          key: ${{ hashFiles('**/poetry.lock') }}-0
+          key: ${{ matrix.python-version }}-${{ hashFiles('**/poetry.lock') }}-1
       - run: |
           pip install virtualenv
           virtualenv .venv
           source .venv/bin/activate
           pip install pip setuptools wheel -U
           poetry install --no-interaction --no-root
         if: steps.cache-venv.outputs.cache-hit != 'true'
-      - run: |
+      - name: Install django version
+        run: |
           source .venv/bin/activate
           pip install "Django==${{ matrix.django-version }}"
+      - run: |
+          source .venv/bin/activate
+          pip install coverage[toml]
       - name: Install DRF 3.11 on Django 2.2
         if: matrix.django-version == '2.2'
         run: pip install "djangorestframework==3.11.1"
-      - run: pip install coverage
-        if: matrix.python-version == '3.10'
       - name: Run tests
         run: |
           source .venv/bin/activate

pyproject.toml

@@ -41,12 +41,12 @@ packages = [
 ]
 
 [tool.poetry.dependencies]
+python = ">=3.6.1,<4.0.0"
 djangorestframework = "*"
-django = "^2.2 || ^3.0 || ^4.0"
+django = "^2.2 || ^3.0"
 inflection = "*"
 openapi-spec-validator = "*"
 prance = "*"
-python = ">=3.6.1,<4.0.0"
 pyYAML = "*"
 
 [tool.poetry.dev-dependencies]
@@ -55,10 +55,10 @@ drf-yasg = "*"
 Faker = "*"
 pre-commit = "*"
 pytest = "*"
-pytest-cov = "*"
 pytest-django = "*"
 pylint = "*"
-coverage = { extras = ["toml"], version = "^6.1.1", python = "3.10" }
+coverage = { extras = ["toml"], version = "^6"}
+pytest-cov = "^2"
 
 [tool.black]
 line-length = 120

test_project/settings.py

@@ -75,7 +75,6 @@
 LANGUAGE_CODE = "en"
 TIME_ZONE = "UTC"
 USE_I18N = True
-USE_L10N = True
 USE_TZ = True
 STATIC_URL = "/test_project/static/"
 STATIC_ROOT = os.path.join(BASE_DIR, "static")