build: more checking of actions with Zizmor

Author: nedbat

.github/workflows/zizmor.yml

@@ -0,0 +1,38 @@
+# Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0
+# For details: https://github.com/nedbat/coveragepy/blob/master/NOTICE.txt
+
+name: Zizmor
+
+on:
+  push:
+    branches:
+      - master
+      - nedbat/*
+  pull_request:
+  workflow_dispatch:
+
+permissions: {}
+
+jobs:
+  zizmor:
+    name: zizmor
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      actions: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          persist-credentials: false
+
+      - name: Install the latest version of uv
+        uses: astral-sh/setup-uv@d4b2f3b6ecc6e67c4457f6d3e41ec42d3d0fcb86 #v5.4.2
+        with:
+          enable-cache: false
+
+      - name: Run zizmor
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: uvx zizmor --pedantic .github/workflows

.github/zizmor.yml

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+# Rules for checking workflows
+# https://woodruffw.github.io/zizmor
+
+rules:
+  unpinned-uses:
+    config:
+      policies:
+        actions/*: hash-pin