feat: 删除无用代码

src/base/single/a/a.js

@@ -10,9 +10,7 @@ import { shortcut } from "../../../core/decorator";
 @shortcut()
 export class A extends BI.Text {
   static xtype = "bi.a";
-  constructor() {
-    super();
-  }
+  
   _defaultConfig() {
     var conf = super._defaultConfig(arguments);
     return BI.extend(conf, {