ci: update macOS images

Author: helgee

.github/workflows/python.yml

@@ -111,9 +111,9 @@ jobs:
     strategy:
       matrix:
         platform:
-          - runner: macos-13
+          - runner: macos-15-intel
             target: x86_64
-          - runner: macos-14
+          - runner: macos-15
             target: aarch64
     steps:
       - uses: actions/checkout@v5