ci: bump the intel macos worker to 15

Author: alexkornitzer

.github/workflows/v2.yml

@@ -123,7 +123,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
   build-mac:
-    runs-on: macos-13
+    runs-on: macos-15
     steps:
       - name: Checkout
         uses: actions/checkout@v6