ci: Update to actions/upload-artifact@v4

Author: rpavlik

.github/workflows/build-macos.yml

@@ -51,7 +51,7 @@ jobs:
 
       # Step 6: Upload the build artifacts
       - name: Upload Artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: OpenXR-Loader-macos-${GITHUB_REF#refs/tags/}
           path: install/OpenXR-Loader-macos-${GITHUB_REF#refs/tags/}.tar.gz