Update actions/checkout to the latest version (#63)

Author: willnet

.github/workflows/ci.yaml

@@ -42,7 +42,7 @@ jobs:
       BUNDLE_GEMFILE: ${{ github.workspace }}/${{ matrix.gemfile }}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v5
       - name: Set up Ruby ${{ matrix.ruby-version }}
         uses: ruby/setup-ruby@v1
         with: