[FIX] Remove duplicate getCommonRoomEvents() event binding for starredMessages

[aKn1ghtOut]

Checklist

• I have read the Contributing Guide
• I have signed the CLA
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works (if applicable)
• I have added necessary documentation (if applicable)
• Any dependent changes have been merged and published in downstream modules

Proposed changes

The getCommonRoomEvents() returned functions were bound to the starredMessages template twice. This was causing some bugs, as detailed in the Issue mentioned below.
I removed the top events call that only bound the getCommonRoomEvents(). Therefore, only one call for the same is left, which is at the end of the file. Having the events bound just once removes the bugs mentioned.

Issue(s)

Closes #20184

gitIssueStarred-2021-01-13_09.58.24.mp4

Steps to test or reproduce

1. Make sure the channel has at least one starred message
2. Go to the menu for the channel ('...')
3. Click on 'Starred Messages'
4. Hover over any starred message to get the menu ('...') and click on it.
5. Click anywhere. The menu just doesn't go away.

Further comments