refactor: 移除用户表和配置表的冗余逻辑

sql/mysql/youlai_admin.sql

@@ -364,8 +364,7 @@ CREATE TABLE `sys_user`  (
                              `update_time` datetime COMMENT '更新时间',
                              `update_by` bigint COMMENT '修改人ID',
                              `is_deleted` tinyint(1) DEFAULT 0 COMMENT '逻辑删除标识(0-未删除 1-已删除)',
-                             PRIMARY KEY (`id`) USING BTREE,
-                             UNIQUE KEY `uk_username` (`username`)
+                            PRIMARY KEY (`id`) USING BTREE
 ) ENGINE = InnoDB CHARACTER SET = utf8mb4 COMMENT = '系统用户表';
 
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