build(deps): upgrade rubygem-deps

Ruby 2.x has passed its end of life and is now unsupported.

.github/workflows/ci.yml

@@ -19,10 +19,6 @@ jobs:
   build:
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        ruby: [2.7, 3]
-
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -32,7 +28,7 @@ jobs:
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: ${{ matrix.ruby }}
+          ruby-version: 3
           bundler-cache: true
 
       - name: Setup Node