chore: Quick CI cleanup (googleapis#22597)

Author: dazuma

.github/workflows/ci.yml

@@ -25,16 +25,13 @@ jobs:
           - os: ubuntu-latest
             ruby: "3.4"
             task: "--include-spec --include-yardoc --include-build"
+            rubyopt: "--enable-frozen-string-literal --debug-frozen-string-literal"
           - os: macos-latest
             ruby: "3.4"
             task: "--include-spec"
           - os: windows-latest
             ruby: "3.4"
             task: "--include-spec"
-          - os: ubuntu-latest
-            ruby: "3.4"
-            task: "--include-spec --include-yardoc --include-build"
-            rubyopt: "--enable-frozen-string-literal --debug-frozen-string-literal"
       fail-fast: false
     runs-on: ${{ matrix.os }}
     steps: