Update CI-mac-x86_64.yml

Author: smistad

.github/workflows/CI-mac-x86_64.yml

@@ -1,4 +1,4 @@
-name: CI macOS 13 x86_64
+name: CI macOS 15 x86_64
 
 on:
   push:
@@ -15,7 +15,7 @@ env:
 
 jobs:
   build:
-    runs-on: macos-13
+    runs-on: macos-15-intel
     steps:
     - uses: actions/checkout@v2   
 
@@ -118,7 +118,7 @@ jobs:
       fail-fast: false
       matrix:
         python-version: ['3.6', '3.10', '3.x']
-    runs-on: macos-13
+    runs-on: macos-15-intel
     steps:
       - name: Download wheel artifact
         uses: actions/download-artifact@v4
@@ -150,7 +150,7 @@ jobs:
       fail-fast: false
       matrix:
         python-version: ['3.10', '3.x']
-    runs-on: macos-13
+    runs-on: macos-15-intel
     steps:
       - name: Checkout
         uses: actions/checkout@v4