macos-13 runner is deprecated, switched to macos-15-intel (#10)

Author: hejamu

.github/workflows/build.yml

@@ -21,8 +21,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        # macos-13 is an intel runner, macos-15 is apple silicon
-        os: [ubuntu-24.04, ubuntu-24.04-arm, windows-2025, macos-13, macos-15]
+        os: [ubuntu-24.04, ubuntu-24.04-arm, windows-2025, macos-15-intel, macos-15]
 
     steps:
       - uses: actions/checkout@v5