ci: bump macos github runner versions

Author: oliverlambson

.github/workflows/CI.yml

@@ -123,9 +123,9 @@ jobs:
     strategy:
       matrix:
         platform:
-          - runner: macos-12
+          - runner: macos-13
             target: x86_64
-          - runner: macos-14
+          - runner: macos-latest
             target: aarch64
     steps:
       - uses: actions/checkout@v4