Merge Request: reset awards on merge request event
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Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards.
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### Description
Awards is useful for code review status. But it becomes completely useless when author updated merge request with new revisions. In this case we have new code in branch and existing rewards makes no sense for team.
### Proposal
Delete all rewards on merge request update event.
### Links / references
Rewards - AKA upvotes / downvotes
Merge request - https://docs.gitlab.com/ce/user/project/integrations/webhooks.html#merge-request-events
issue