Sync branches into databases (#22743)

Related #14180
Related #25233 
Related #22639
Close #19786
Related #12763 

This PR will change all the branches retrieve method from reading git
data to read database to reduce git read operations.

- [x] Sync git branches information into database when push git data
- [x] Create a new table `Branch`, merge some columns of `DeletedBranch`
into `Branch` table and drop the table `DeletedBranch`.
- [x] Read `Branch` table when visit `code` -> `branch` page
- [x] Read `Branch` table when list branch names in `code` page dropdown
- [x] Read `Branch` table when list git ref compare page
- [x] Provide a button in admin page to manually sync all branches.
- [x] Sync branches if repository is not empty but database branches are
empty when visiting pages with branches list
- [x] Use `commit_time desc` as the default FindBranch order by to keep
consistent as before and deleted branches will be always at the end.

---------

Co-authored-by: Jason Song <i@wolfogre.com>

models/migrations/migrations.go

@@ -509,6 +509,8 @@ var migrations = []Migration{
 	NewMigration("Add TriggerEvent to action_run table", v1_21.AddTriggerEventToActionRun),
 	// v263 -> v264
 	NewMigration("Add git_size and lfs_size columns to repository table", v1_21.AddGitSizeAndLFSSizeToRepositoryTable),
+	// v264 -> v265
+	NewMigration("Add branch table", v1_21.AddBranchTable),
 }
 
 // GetCurrentDBVersion returns the current db version