Pin GitHub actions to commit SHA

https://blog.rafaelgss.dev/why-you-should-pin-actions-by-commit-hash

.github/workflows/update.yml

@@ -17,17 +17,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3
         with:
           fetch-depth: 0
 
       - name: Setup Node.js
-        uses: actions/setup-node@v3
+        uses: actions/setup-node@1a4442cacd436585916779262731d5b162bc6ec7 # v3
         with:
           node-version: 18
 
       - name: Check cache
-        uses: actions/cache@v3
+        uses: actions/cache@e12d46a63a90f2fae62d114769bbf2a179198b5c # v3
         id: npm-cache
         with:
           path: '**/node_modules'
@@ -41,7 +41,7 @@ jobs:
         run: npm run start
 
       - name: Checkout gh-pages branch
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3
         with:
           ref: gh-pages
           path: gh-pages