Update authentication.yml

Author: ncooke3

.github/workflows/authentication.yml

@@ -43,6 +43,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@master
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.4.app/Contents/Developer
       - name: Setup
         run: |
           gem install xcpretty