fix(webcam): key list not provided

[pedrobmarin]

userName is a list, and its contents must have an unique key.

Warning: Each child in a list should have a unique "key" prop.

Check the render method of `UserName`. See https://fb.me/react-warning-keys for more information.
    in span (created by UserName)
    in UserName (created by UserDropdown)
    in div (created by UserDropdown)
    in div (created by UserDropdown)
    in div (created by UserDropdown)
    in div (created by BBBMenu)
    in div (created by BBBMenu)
    in BBBMenu (created by Context.Consumer)
    in injectIntl(BBBMenu) (created by UserDropdown)
    in UserDropdown (created by Context.Consumer)

To Reproduce
Steps to reproduce the behavior:

1. Join as desktop user
2. Join as mobile user
3. The mobile user then shares his webcam
4. The desktop user now see two labels underneath
   his name: Webcam | Mobile
5. The desktop user's console shows a warning

cc @frankemax

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

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