[google_maps_flutter] Disable XCUITest (flutter#4490)

Temporarily disables the only XCUITest for Maps until the cause of
flutter/flutter#93325 is found and fixed, in
order to re-open the tree.

packages/google_maps_flutter/google_maps_flutter/example/ios/RunnerUITests/GoogleMapsUITests.m

@@ -42,7 +42,8 @@ - (void)setUp {
                                       }];
 }
 
-- (void)testUserInterface {
+// Temporarily disabled due to https://github.com/flutter/flutter/issues/93325
+- (void)skip_testUserInterface {
   XCUIApplication* app = self.app;
   XCUIElement* userInteface = app.staticTexts[@"User interface"];
   if (![userInteface waitForExistenceWithTimeout:30.0]) {