[Infra] Update combine.yml

.github/workflows/combine.yml

@@ -88,6 +88,8 @@ jobs:
       run: scripts/setup_bundler.sh
     - name: Install xcpretty
       run: gem install xcpretty
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.3.app/Contents/Developer
     - name: Install Secret GoogleService-Info.plist
       run: scripts/decrypt_gha_secret.sh scripts/gha-encrypted/storage-db-plist.gpg \
           FirebaseStorage/Tests/Integration/Resources/GoogleService-Info.plist "$plist_secret"