Merge pull request #1120 from ruby/claude/kind-gates-128123

Test on macos-15 instead of the retired macos-14

Author: hsbt

.github/workflows/ci.yml

@@ -34,7 +34,7 @@ jobs:
           - { os: ubuntu-24.04-arm, ruby: 3.4 }
           - { os: ubuntu-latest  , ruby: 3.4, env: "JSON_DISABLE_SIMD=1" }
           - { os: ubuntu-latest  , ruby: 3.4, env: "JSON_DEBUG=1" }
-          - { os: macos-14, ruby: 3.4 }
+          - { os: macos-15, ruby: 3.4 }
           - { os: windows-latest , ruby: mswin     } # ruby/ruby windows CI
           - { os: macos-latest  , ruby: jruby-9.4 } # Ruby 3.1
           - { os: ubuntu-latest  , ruby: jruby-9.4 } # Ruby 3.1