BottomNavigationView should have a method to get the item (and change the text)

Hello,

I currently have a tab with the user location, and would like to dynamically change the text of the BottomNavigationItem.

Do you plan to add something like:

bottomNavigationView.getItem(0).setTitle("NewTitle")?

Thank a lot for the awesome lib!

Start by locating the BottomNavigationView and BottomNavigationItem implementations in the repository, then inspect how navigation items are created and exposed. Confirm that a public item lookup and title update can be supported, and verify the completed behavior with the project's existing tests or Android sample.

Written by the indexing model from the issue text.