Fill head commit to in payload when notifying push commits for mirroring (#23215)
Just like what has been done when pushing manually:
7a5af25592/services/repository/push.go (L225-L226)
Before:
<img width="448" alt="image"
src="https://user-images.githubusercontent.com/9418365/222100123-cd4839d1-2d4d-45f7-b7a0-0cbc73162b44.png">
After:
<img width="448" alt="image"
src="https://user-images.githubusercontent.com/9418365/222100225-f3c5bb65-7ab9-41e2-8e39-9d84c23c352d.png">
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Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
7b9e23cc1d
