pin ruby/setup-ruby version

Author: gbkomoju

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/checkout@v6.0.2
         with:
           persist-credentials: false
-      - uses: ruby/setup-ruby@v1
+      - uses: ruby/setup-ruby@afeafc3d1ab54a631816aba4c914a0081c12ff2f # v1.310.0
         with:
           ruby-version: '3.2'
       - name: Build gem