[Glitch] Change dropdown icon above compose form from ellipsis to bars in web UI

Port 0512537eb6 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/features/compose/components/action_bar.jsx

@@ -62,7 +62,7 @@ class ActionBar extends PureComponent {
     return (
       <div className='compose__action-bar'>
         <div className='compose__action-bar-dropdown'>
-          <DropdownMenuContainer items={menu} icon='ellipsis-v' size={18} direction='right' />
+          <DropdownMenuContainer items={menu} icon='bars' size={18} direction='right' />
         </div>
       </div>
     );