Description:

Inside app/livechat/client/ui.js on line 41, tabBar Icon is set to lightbulb. But it is missing from app/ui-master/public/icons. So add svg for it

Steps to reproduce:

1. Open live chat for any user
2. See tabBar

Expected behavior:

Icon should be there

Actual behavior:

Server Setup Information:

• Version of Rocket.Chat Server: 1.0.0-develop
• Operating System: MacOs
• Deployment Method: Meteor
• Number of Running Instances: 1
• DB Replicaset Oplog: Enables
• NodeJS Version: 8.11.4
• MongoDB Version: 3.6

Additional Text

Will add a PR for the same