[DB] Ensure forgejo migration up to date (squash)

- Backport https://codeberg.org/forgejo/forgejo/pulls/1849
- Hook Forgejo's `EnsureUpToDate` to Gitea's `EnsureUpToDate`, such that
the Forgejo migrations are also being checked to be up to date.
- I'm not sure how I missed this and if this has caused any problems,
but due to the lack of any open issue about it it seems to not be a big
problem.

(cherry picked from commit 6c65b6dcf6)

models/migrations/migrations.go

@@ -544,7 +544,7 @@ func EnsureUpToDate(x *xorm.Engine) error {
 		return fmt.Errorf(`Current database version %d is not equal to the expected version %d. Please run "forgejo [--config /path/to/app.ini] migrate" to update the database version`, currentDB, expected)
 	}
 
-	return nil
+	return forgejo_migrations.EnsureUpToDate(x)
 }
 
 // Migrate database to current version