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>

routers/web/repo/issue.go

@@ -785,7 +785,13 @@ func RetrieveRepoMetas(ctx *context.Context, repo *repo_model.Repository, isPull
 		return nil
 	}
 
-	brs, _, err := ctx.Repo.GitRepo.GetBranchNames(0, 0)
+	brs, err := git_model.FindBranchNames(ctx, git_model.FindBranchOptions{
+		RepoID: ctx.Repo.Repository.ID,
+		ListOptions: db.ListOptions{
+			ListAll: true,
+		},
+		IsDeletedBranch: util.OptionalBoolFalse,
+	})
 	if err != nil {
 		ctx.ServerError("GetBranches", err)
 		return nil