Add code formatting to the CI pipeline

Any PR will now have code formatting automatically applied.

.github/workflows/main.yml

@@ -0,0 +1,29 @@
+name: Code formatter for PRs
+on: pull_request
+jobs:
+  format-code:
+    runs-on: ubuntu-latest
+    permissions:
+      # Give the default GITHUB_TOKEN write permission to commit and push the
+      # added or changed files to the repository.
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.head_ref }}
+      - name: Install Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install ruff
+      # Update output format to enable automatic inline annotations.
+      - name: Run Ruff
+        run: ruff format
+      - name: Commit formatting changes
+        uses: stefanzweifel/git-auto-commit-action@v5
+        with:
+          commit_message: Apply code formatting
+          branch: ${{ github.head_ref }}