Re-add test step to CI

.gitea/workflows/build-docker.yml

@@ -2,12 +2,20 @@ name: Django CI/CD
 
 on:
   push:
-    branches: [ main ]
     paths-ignore: [ 'README.md' ]
 
 jobs:
+  test:
+    runs-on: python:3.12
+    steps:
+    - python -m pip install poetry
+    - poetry install
+    - poetry env info
+    - poetry run python manage.py migrate
+    - poetry run pytest
   build-and-push:
     runs-on: ubuntu-latest
+    if: github.ref == 'refs/heads/main'
     steps:
     - name: Checkout
       uses: actions/checkout@v4