Fix default Accounts destination (#507)

Author: simona-anomis

NavigationCodelab/app/src/main/java/com/example/compose/rally/RallyActivity.kt

@@ -49,7 +49,7 @@ fun RallyApp() {
         val currentBackStack by navController.currentBackStackEntryAsState()
         val currentDestination = currentBackStack?.destination
         val currentScreen =
-            rallyTabRowScreens.find { it.route == currentDestination?.route } ?: Overview
+            rallyTabRowScreens.find { it.route == currentDestination?.route } ?: Accounts
 
         Scaffold(
             topBar = {