Remove legacy +build: constraint (#19582)

Go 1.17 and later use modern `//go:build` constraints, the old `// +build:` constraints should be removed.

modules/setting/database_sqlite.go

@@ -1,5 +1,4 @@
 //go:build sqlite
-// +build sqlite
 
 // Copyright 2014 The Gogs Authors. All rights reserved.
 // Use of this source code is governed by a MIT-style