Related to #26239
This PR makes some fixes:
- do not show the prompt for mirror repos and repos with pull request
units disabled
- use `commit_time` instead of `updated_unix`, as `commit_time` is the
real time when the branch was pushed
This PR will display a pull request creation hint on the repository home
page when there are newly created branches with no pull request. Only
the recent 6 hours and 2 updated branches will be displayed.
Inspired by #14003
Replace #14003Resolves#311Resolves#13196Resolves#23743
co-authored by @kolaente