title: Flutter - How to hide/remove title of BottomNavigationBarItem
body: <p>so i have this flutter app, and i'm trying to hide or remove the title. I tried leaving the title as an empty string i.e. <code>new Text("")</code> but that messed with the alignment of the navbar.</p>
  
  <p>Desired Outcome:</p>
  
  <p><a href="https://i.stack.imgur.com/Ux5Vi.png" rel="noreferrer"><img src="https://i.stack.imgur.com/Ux5Vi.png" alt="Hers&#39;s what i want to acheive"></a></p>
  
  <p>What i'm getting (if i leave the title as empty string):</p>
  
  <p><a href="https://i.stack.imgur.com/oIqoS.png" rel="noreferrer"><img src="https://i.stack.imgur.com/oIqoS.png" alt="enter image description here"></a>:</p>