Really setup Xcode 15.3 [skip ci]

Author: acgetchell

.github/workflows/macos.yml

@@ -16,8 +16,10 @@ jobs:
           fetch-depth: 0
           submodules: true
 
-      - name: Select Xcode 15.3 (Apple Clang 17)
-        run: sudo xcode-select -s /Applications/Xcode_15.3.app
+      - name: Setup Xcode 15.3 (Apple Clang 17)
+        uses: maxim-lobanov/setup-xcode@v1
+        with:
+          xcode-version: '15.3'
 
       - name: Verify Clang version
         run: clang --version