👷 Add GitHub Actions workflow to lint backend apart from tests (#1358)

.github/workflows/lint-backend.yml

@@ -0,0 +1,40 @@
+name: Lint Backend
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types:
+      - opened
+      - synchronize
+
+jobs:
+
+  lint-backend:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      - name: Install uv
+        uses: astral-sh/setup-uv@v2
+        with:
+          version: "0.4.15"
+      - run: uv run bash scripts/lint.sh
+        working-directory: backend
+
+  # https://github.com/marketplace/actions/alls-green#why
+  lint-backend-alls-green:  # This job does nothing and is only used for the branch protection
+    if: always()
+    needs:
+      - lint-backend
+    runs-on: ubuntu-latest
+    steps:
+      - name: Decide whether the needed jobs succeeded or failed
+        uses: re-actors/alls-green@release/v1
+        with:
+          jobs: ${{ toJSON(needs) }}