Fixing build matrix

.github/workflows/django.yml

@@ -30,39 +30,12 @@ jobs:
     strategy:
       max-parallel: 4
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
-        django-version: [2.0, 2.1, 2.2, 3.0, 3.1, 3.2, 4.0]
+        python-version: [3.7, 3.8, 3.9, "3.10"]
+        django-version: [3.2, 4.0]
         exclude:
         # Django 4.0 is compatible with Python 3.8+
-        - python-version: "3.6"
-          django-version: "4.0"
         - python-version: "3.7"
           django-version: "4.0"
-        # Python 3.8 is compatible with Django 2.2+
-        - python-version: "3.8"
-          django-version: "2.0"
-        - python-version: "3.8"
-          django-version: "2.1"
-        # Python 3.9 is compatible with Django 3.1+
-        - python-version: "3.9"
-          django-version: "2.0"
-        - python-version: "3.9"
-          django-version: "2.1"
-        - python-version: "3.9"
-          django-version: "2.2"
-        - python-version: "3.9"
-          django-version: "3.0"
-        # Python 3.10 is compatible with Django 3.2+
-        - python-version: "3.10"
-          django-version: "2.0"
-        - python-version: "3.10"
-          django-version: "2.1"
-        - python-version: "3.10"
-          django-version: "2.2"
-        - python-version: "3.10"
-          django-version: "3.0"
-        - python-version: "3.10"
-          django-version: "3.1"
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}
@@ -84,12 +57,12 @@ jobs:
     - name: Run Tests psql
       run: |
         coverage run -a tests/runtests.py -d psql
-      env: 
+      env:
         DB_USER: postgres
         DB_PASSWORD: postgres
     - name: Run Tests mysql
       run: |
         coverage run -a tests/runtests.py -d mysql
-      env: 
+      env:
         DB_USER: root
         DB_PASSWORD: mysql