Commit modal: condense commit confirmation alert
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# Context
In https://gitlab.com/gitlab-org/gitlab/-/merge_requests/206943#note_2807517380, the success confirmation that appears after the user edits a file and commits changes was condensed.
> My only concern would be the loss of the `Create merge request` button in the new success banner. This gives users a clear path forward, and encourages the usage of merge requests for good development hygiene / encouraging more usage of the tools in GitLab's ecosystem.
| Before | After |
|--------|-------|
| {width="1296" height="805"} | {width="1295" height="834"} |
# Design recommendation
Update the text in the banner, and add the `Create merge request` button if the user did not create a merge request:
<table>
<tr>
<th>User did create a merge request</th>
<th>User did NOT create a merge request</th>
</tr>
<tr>
<td>
You successfully committed and pushed your changes to `branch-name-here` \[copy button\].
</td>
<td>
You successfully committed and pushed your changes to `branch-name-here` \[copy button\].
`Create merge request`
</td>
</tr>
</table>
issue