Update documentation/ui/transitions.md

Co-authored-by: Manuel Vivo <[email protected]>

documentation/ui/transitions.md

@@ -87,7 +87,8 @@ class ParentNode(
          navModel = backStack,
          // or no transitionHandler at all. Using a slider will make the shared element slide away
          // with the rest of of the content.
-         transitionHandler = rememberBackStackFader()
+         transitionHandler = rememberBackStackFader(),
+         withSharedElementTransition = true
       )
    }
 }