add github actions

.github/workflows/checks.yml

@@ -0,0 +1,20 @@
+name: Checks
+
+on: [push]
+
+jobs:
+    test-lint:
+        name: Test and Lint
+        runs-on: ubuntu-20.04
+        steps:
+            - name: Login to Docker Hub
+              uses: docker/login-action@v2
+              with:
+                username: ${{ env.DOCKERHUB_USER }}
+                password: ${{ env.DOCKERHUB_TOKEN }}
+            - name: Checkout
+              uses: actions/checkout@v2
+            - name: Test
+              run: docker compose run --rm app sh -c "python manage.py test"
+            - name: Lint
+              run: docker compose run --rm app sh -c "flake8"