Add ruby 3.4 to build matrix

Author: rmm5t

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: ["2.4", "2.5", "2.6", "2.7", "3.0", "3.1", "3.2", "3.3"]
+        ruby: ["2.4", "2.5", "2.6", "2.7", "3.0", "3.1", "3.2", "3.3", "3.4"]
 
     steps:
       # https://github.com/marketplace/actions/checkout