Add Ruby 3.4 to test matrix

Author: brucebolt

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [3.2, 3.3]
+        ruby: [3.2, 3.3, 3.4]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4