【修复】SYSTEM：id 获取不到用户引发的 NPE 异常

yudao-module-system/yudao-module-system-biz/src/main/java/cn/iocoder/yudao/module/system/controller/admin/user/UserController.java

@@ -119,7 +119,9 @@ public class UserController {
     @PreAuthorize("@ss.hasPermission('system:user:query')")
     public CommonResult<UserRespVO> getUser(@RequestParam("id") Long id) {
         AdminUserDO user = userService.getUser(id);
-        if (ObjectUtil.isEmpty(user)) return CommonResult.success(null);
+        if (user == null) {
+            return success(null);
+        }
         // 拼接数据
         DeptDO dept = deptService.getDept(user.getDeptId());
         return success(UserConvert.INSTANCE.convert(user, dept));