Add zizmor action

Author: trinistr

.github/workflows/zizmor.yaml

@@ -0,0 +1,23 @@
+name: GitHub Actions Security Analysis with zizmor 🌈
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["**"]
+
+permissions: {}
+
+jobs:
+  zizmor:
+    runs-on: ubuntu-latest
+    permissions:
+      security-events: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          persist-credentials: false
+
+      - name: Run zizmor 🌈
+        uses: zizmorcore/zizmor-action@5ca5fc7a4779c5263a3ffa0e1f693009994446d1 # v0.1.2

.github/zizmor.yml

@@ -0,0 +1,8 @@
+rules:
+  unpinned-uses:
+    config:
+      policies:
+        # Default policy for official actions.
+        actions/*: ref-pin
+        # Allow Ruby's official setup action, as it is continuously updated with new versions.
+        ruby/setup-ruby: ref-pin