Fix #21740.
Updated the Pull Request template so that the 'Update branch by merge'
button is visible for WIP PR's. Making the behaviour match a non WIP-PR.
Previous WIP page with changes pending on the branch:
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Updated UI adding the update button:
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## Notes
* have not removed the **$canAutoMerge** variable from the pull.tmpl on
this
[line](
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.. | ||
add_reaction.tmpl | ||
attachments.tmpl | ||
comments.tmpl | ||
comments_delete_time.tmpl | ||
context_menu.tmpl | ||
pull.tmpl | ||
pull_merge_instruction.tmpl | ||
reactions.tmpl | ||
reference_issue_dialog.tmpl | ||
sidebar.tmpl | ||
update_branch_by_merge.tmpl |