Break long line in workflow

Author: eregon

.github/workflows/test.yml

@@ -18,7 +18,12 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-18.04, ubuntu-20.04, ubuntu-22.04, macos-10.15, macos-11, macos-12, windows-2019, windows-2022 ]
-        ruby: [ '1.9', '2.0', '2.1', '2.2', '2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2', ruby-head, jruby, jruby-head, truffleruby, truffleruby-head, truffleruby+graalvm, truffleruby+graalvm-head ]
+        ruby: [
+          '1.9', '2.0', '2.1', '2.2', '2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2', ruby-head,
+          jruby, jruby-head,
+          truffleruby, truffleruby-head,
+          truffleruby+graalvm, truffleruby+graalvm-head
+        ]
         include:
         - { os: windows-2019, ruby: mingw }
         - { os: windows-2019, ruby: mswin }