use Xcode 16.0 or higher for firebase-ios-sdk 11.12.0+

Author: fumito-ito

.github/workflows/swift.yml

@@ -13,6 +13,8 @@ jobs:
     runs-on: macos-14
     steps:
     - uses: actions/checkout@v4
+    - name: Change Xcode version
+      run: sudo xcode-select -s /Applications/Xcode_16.2.app
     - name: Install swiftlint
       run: |
         brew update