Update ci: pin actions versions to a specific commit (#5)

Author: sofiabobadilla

.github/workflows/deploy.yml

@@ -12,13 +12,13 @@ jobs:
 
     steps:
       - name: Clone repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
         with:
           fetch-depth: 0
           submodules: true
 
       - name: Set up Ruby
-        uses: ruby/setup-ruby@v1
+        uses: ruby/setup-ruby@ae195bbe749a7cef685ac729197124a48305c1cb # v1
         with:
           ruby-version: '3.3'
           bundler-cache: true
@@ -32,7 +32,7 @@ jobs:
         run: make
 
       - name: Deploy
-        uses: peaceiris/actions-gh-pages@v3
+        uses: peaceiris/actions-gh-pages@373f7f263a76c20808c831209c920827a82a2847 # v3
         if: success()
         with:
           allow_empty_commit: false