fix(#IVY9T): 字典表维护页面字典代码长度大于50时字符串被截断

#Issue
https://gitee.com/LongbowEnterprise/BootstrapAdmin/issues/IVY9T?from=project-issue

#Comment
close #IVY9T

Bootstrap.DataAccess/Dict.cs

@@ -35,7 +35,8 @@ namespace Bootstrap.DataAccess
         {
             if (dict.Category.Length > 50) dict.Category = dict.Category.Substring(0, 50);
             if (dict.Name.Length > 50) dict.Name = dict.Name.Substring(0, 50);
-            if (dict.Code.Length > 50) dict.Code = dict.Code.Substring(0, 50);
+            
+            if (dict.Code.Length > 500) dict.Code = dict.Code.Substring(0, 500);
 
             DbManager.Create().Save(dict);
             return true;