Pin GitHub Actions to full-length commit SHAs (#3625)

Author: danfiedler-msft

.github/dependabot.yml

@@ -14,6 +14,8 @@ updates:
       github-actions:
         patterns:
           - '*'
+    cooldown:
+      default-days: 7
 
   - package-ecosystem: 'devcontainers'
     directory: '/'

.github/workflows/close-preview.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     if: github.repository == 'microsoft/TypeScript-Website'
     steps:
-      - uses: Azure/static-web-apps-deploy@v1
+      - uses: Azure/static-web-apps-deploy@4d27395796ac319302594769cfe812bd207490b1 # v1
         with:
           azure_static_web_apps_api_token: ${{ secrets.AZURE_STATIC_WEB_APPS_API_TOKEN_PREVIEW }}
           action: close

.github/workflows/deploy-preview.yml

@@ -142,7 +142,7 @@ jobs:
       - name: Deploy
         id: deploy
         if: ${{ steps.get-info.outputs.result != 'null' }}
-        uses: Azure/static-web-apps-deploy@v1
+        uses: Azure/static-web-apps-deploy@4d27395796ac319302594769cfe812bd207490b1 # v1
         with:
           azure_static_web_apps_api_token: ${{ secrets.AZURE_STATIC_WEB_APPS_API_TOKEN_PREVIEW }}
           # Unsetting the repo token so we can control commenting ourselves.