Add Ruby 3.4 to the CI matrix

This PR adds Ruby 3.4 to the CI matrix.

Author: and9000

.github/workflows/ruby.yml

@@ -28,6 +28,7 @@ jobs:
           - 3.1
           - 3.2
           - 3.3
+          - 3.4
         resque-version:
           - "master"
           - "~> 2.4.0"
@@ -47,6 +48,8 @@ jobs:
             rufus-scheduler: 3.2
           - ruby-version: 3.3
             rufus-scheduler: 3.2
+          - ruby-version: 3.4
+            rufus-scheduler: 3.2
 
           - ruby-version: 2.3
             resque-version: "~> 1.27"