ci: add ci workflow

.gitea/workflows/ci.yaml

@@ -0,0 +1,21 @@
+name: Continuous Integration
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  lint_n_build:
+    runs-on: linux
+    steps:
+      - name: Git checkout
+        uses: actions/checkout@v6
+      - name: Setup python
+        uses: actions/setup-python@v6
+      - name: Install systemdlint
+        run: pip install systemdlint
+      - name: Lint systemd files
+        run: systemdlint files/systemd/certbot-renew.service files/systemd/certbot-renew.timer
+      - name: Lint shell scripts
+        run: shellcheck files/sbin/certbot-renew