refactor(database/gdb): add quote for FieldsPrefix and FieldsExPrefix

[hicolin]

Code example：

	var res *BasicInfo
	err := g.DB().Model("basic_info").
		FieldsPrefix("basic_info", basicInfoColumns).
		Where("id", 35813305356386305).Scan(&res)
	if err != nil {
		panic(err)
	}
	g.Dump(res)

SQL generated before modification ：

SELECT basic_info.id,basic_info.full_name,basic_info.contact FROM `basic_info` WHERE (`id`=35813305356386305) AND `delete_time` IS NULL LIMIT 1

SQL generated after modification：

SELECT `basic_info`.`id`,`basic_info`.`full_name`,`basic_info`.`contact` FROM `basic_info` WHERE (`id`=35813305356386305) AND `delete_time` IS NULL LIMIT 1

[gqcn]

@hicolin The CI failed, you need update the expect result of the unit testing case for the CLI, too.