Try newer jruby

Author: joshuaclayton

.github/workflows/ci.yml

@@ -11,14 +11,18 @@ jobs:
       fail-fast: false
       matrix:
         ruby:
-          - jruby-19mode
+          - jruby-9.1.17.0
           - "1.9"
           - "2.0"
           - "2.1"
           - "2.2"
           - "2.3"
           - "2.4"
           - "2.5"
+          - "2.6"
+          - "2.7"
+          - "3.0"
+          - "3.1"
 
     runs-on: 'ubuntu-latest'