Pending comments on merge request threads don't show if the comment will resolve the thread
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When adding multiple comments/replies to an MR we can choose to batch those replies.
If one of those comments/replies would resolve a thread, that is not visible once the comment is saved but pending :slight_smile:
See images below for an example:
- I write a comment, check the `Resolve thread` checkbox and click `Add to review` (or `Start review`) to save the pending comments

- The fact that the comment will resolve the thread is not visible on the pending comment

- Using the edit button to change the comment shows that the checkbox is indeed still checked (so the status is saved)

## Proposal
Use something similar to what we already have to show the result of a slash command to let the user know that the comment will resolve the thread :slight_smile:
Similar to this:

But with a message like `Solves the thread.`
issue