Exclude older versions unsupported by setup-ruby

.github/workflows/test.yml

@@ -3,12 +3,23 @@ name: test
 on: [push, pull_request]
 
 jobs:
+  ruby-versions:
+    if: ${{ startsWith(github.repository, 'ruby/') || github.event_name != 'schedule' }}
+    uses: ruby/actions/.github/workflows/ruby_versions.yml@master
+    with:
+      engine: cruby
+      min_version: 2.4
+
   build:
+    needs: ruby-versions
     name: build (${{ matrix.ruby }} / ${{ matrix.os }})
     strategy:
       matrix:
-        ruby: [ 3.1, '3.0', 2.7, 2.6, 2.5, 2.4, head ]
+        ruby: ${{ fromJson(needs.ruby-versions.outputs.versions) }}
         os: [ ubuntu-latest, macos-latest ]
+        exclude:
+          - { os: macos-latest, ruby: 2.4 }
+          - { os: macos-latest, ruby: 2.5 }
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v4