.github/workflows/main.yml - Add test target Ruby versions

Author: epaew

.github/workflows/main.yml

@@ -14,7 +14,13 @@ jobs:
     strategy:
       matrix:
         ruby:
-          - '3.2.8'
+          - '2.7.8'
+          - '3.0.7'
+          - '3.1.7'
+          - '3.2.10'
+          - '3.3.10'
+          - '3.4.9'
+          - '4.0.1'
 
     steps:
       - uses: actions/checkout@v4