workflow: Use macos-15

Author: mingchen

.github/workflows/build_and_test.yml

@@ -10,7 +10,7 @@ concurrency:
 jobs:
   build:
     name: Build and Test (Xcode ${{ matrix.xcode }})
-    runs-on: macos-14
+    runs-on: macos-15
     continue-on-error: true
     strategy:
       matrix: