ci: use macos-15 (#873)

Author: mkniewallner

.github/workflows/main.yml

@@ -54,7 +54,7 @@ jobs:
           - name: linux
             image: ubuntu-24.04
           - name: macos
-            image: macos-14
+            image: macos-15
           - name: windows
             image: windows-2022
         python-version: ['3.9', '3.10', '3.11', '3.12', '3.13-dev', 'pypy3.10']

.github/workflows/release.yml

@@ -109,7 +109,7 @@ jobs:
           path: dist
 
   macos:
-    runs-on: macos-14
+    runs-on: macos-15
     needs: [set-version]
     strategy:
       matrix: