Summarize similar system notes for pushes
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Pushing changes to merge request will create a new system note, which is great!
We should be smarter about how we render these notes. For example, if **the same user** pushes more changes to the merge request over a few hours or days without any activity, we can summarize the system notes so that the timeline is easier to read.
### Proposal
Summarize push system notes if:
1. pushes come immediately after each other - no any other events between them
1. pushes lay in a small time window (1 minute - 30 minutes)
### Links / references
issue