[skip] Added Ruby 3.0 to test matrix (1m)

Author: kobsy

.github/workflows/ci.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby-version: [ "2.6", "2.7" ]
+        ruby-version: [ "2.6", "2.7", "3.0" ]
 
     steps:
       - name: Checkout