ci: pin all GitHub Actions to commit SHAs (#1875)

.github/workflows/publish-docs-manually.yml

@@ -9,20 +9,20 @@ jobs:
     permissions:
       contents: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
       - name: Configure Git Credentials
         run: |
           git config user.name github-actions[bot]
           git config user.email 41898282+github-actions[bot]@users.noreply.github.com
 
       - name: Install uv
-        uses: astral-sh/setup-uv@v3
+        uses: astral-sh/setup-uv@caf0cab7a618c569241d31dcd442f54681755d39 # v3.2.4
         with:
           enable-cache: true
           version: 0.9.5
 
       - run: echo "cache_id=$(date --utc '+%V')" >> $GITHUB_ENV
-      - uses: actions/cache@v4
+      - uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
         with:
           key: mkdocs-material-${{ env.cache_id }}
           path: .cache