[CI] Adds jruby 9.4

Author: picandocodigo

.github/workflows/jruby.yml

@@ -16,6 +16,8 @@ jobs:
       RAILS_VERSIONS: '5.0,6.0'
     strategy:
       fail-fast: false
+    matrix:
+      ruby: [ 'jruby-9.3', 'jruby-9.4' ]
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
@@ -30,7 +32,7 @@ jobs:
         stack-version: 7.17-SNAPSHOT
     - uses: ruby/setup-ruby@v1
       with:
-        ruby-version: jruby-9.3
+        ruby-version: ${{ matrix.ruby }}
     - name: Bundle
       run: |
         gem install bundler