Test code with GitHub Actions and run CodeQL weekly

.github/workflows/build.yml

@@ -0,0 +1,21 @@
+---
+name: Test code
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - run: pipx install poetry
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.10"
+          cache: 'poetry'
+      - run: poetry install
+      - run: poetry run pytest