title: React Navigation header title in nested tab navigator
body: <p>I have a Tab Navigator inside a Stack Navigator and I want the header title to be dynamically configured as the title of the tab selected. Like there's 3 tabs: Home, Profile, Add Item and I want the header title to be "Home" when in the home tab, "Profile" when in the profile tab.</p>
  
  <p>I tried using onStateChange on the root navigator and setOptions on the tab navigator but onStateChange is only available in the  and not in the nested navigators.</p>
  
  <p>Is their anyway I can archieve this?</p>
  
  <p>The navigator config is:</p>
  
  <pre><code>const TabNav = (
     &lt;Tab.Navigator&gt;
        &lt;Tab.Screen name='Home' component={HomeScreen}/&gt;
        &lt;Tab.Screen name='Profile' component={ProfileScreen}/&gt;
        &lt;Tab.Screen name='Add Item' component={AddItemScreen}/&gt;
     &lt;/Tab.Navigator&gt;
  )
  
  &lt;NavigationContainer&gt;
     &lt;Stack.Navigator&gt;
        &lt;Stack.Screen name='Login' component={LoginScreen}/&gt;
        &lt;Stack.Screen name='App' component={TabNav}/&gt;
     &lt;/Stack.Navigator&gt;
  &lt;/NavigationContainer&gt;
  </code></pre>