Changed MacOS intel build to use macos-15-intel runner since macos-13 is retired

Author: azonenberg

.github/workflows/build-macos-intel.yml

@@ -8,7 +8,7 @@ on:
 jobs:
 
   macOS:
-    runs-on: macos-13
+    runs-on: macos-15-intel
 
     steps: