fix(Drawer): closeIcon customization is invalid (#5616)

Author: buqiyuan

components/drawer/index.tsx

@@ -271,7 +271,7 @@ const Drawer = defineComponent({
       return (
         closable && (
           <button key="closer" onClick={close} aria-label="Close" class={`${prefixCls}-close`}>
-            {$closeIcon === undefined ? <CloseOutlined></CloseOutlined> : null}
+            {$closeIcon === undefined ? <CloseOutlined></CloseOutlined> : $closeIcon}
           </button>
         )
       );