人员信息修改时，校验账号是否已存在

zd-modules/zd-modules-system/src/main/java/com/zd/system/controller/SysTeacherController.java

@@ -203,6 +203,8 @@ public class SysTeacherController extends BaseController {
         } else if (StringUtils.isNotEmpty(user.getEmail())
                 && UserConstants.NOT_UNIQUE.equals(sysTeacherService.checkEmailUnique(user))) {
             return AjaxResult.error("修改用户'" + user.getUserName() + "'失败，邮箱账号已存在");
+        }else if (UserConstants.NOT_UNIQUE.equals(sysTeacherService.checkUserNameUnique(user.getUserName()))) {
+            return AjaxResult.error("修改用户'" + user.getUserName() + "'失败，账号已存在");
         }
         user.setUpdateBy(SecurityUtils.getUsername());
         return toAjax(sysTeacherService.update(user));