Implement sync push mirror on commit (go-gitea#19411)

Support synchronizing with the push mirrors whenever new commits are pushed or synced from pull mirror.

Related Issues: go-gitea#18220

Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

Author: 4 people

models/migrations/v219.go

@@ -9,7 +9,6 @@ import (
 
 	"code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/modules/timeutil"
-
 	"xorm.io/xorm"
 )