Test against Ruby 3.0 also

ashmckenzie · ashmckenzie · commit 10b61aed0064 · 2023-01-10T14:05:45.000+11:00
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
@@ -57,6 +57,7 @@ tests:
   parallel:
     matrix:
       - GO_VERSION: ["1.17", "1.18", "1.19"]
+      - RUBY_VERSION: ["2.7", "3.0"]
   script:
     - make verify test
   after_script:
