CI: update macos runner images

Author: lonvia

.github/workflows/ci.yml

@@ -301,7 +301,7 @@ jobs:
                       deps: develop
                       flavour: linux
                     - compiler: macos-intel
-                      platform: macos-13
+                      platform: macos-15-intel
                       python: "3.10"
                       deps: develop
                       flavour: macos