docs(popup): add defaultVisible description (#6099)

Author: RSS1102

packages/components/popup/popup.en-US.md

@@ -22,6 +22,7 @@ showArrow | Boolean | false | \- | N
 trigger | String | hover | options: hover/click/focus/mousedown/context-menu | N
 triggerElement | String / Slot / Function | - | Typescript：`string \| TNode`。[see more ts definition](https://github.com/Tencent/tdesign-vue-next/blob/develop/packages/components/common.ts) | N
 visible | Boolean | - | `v-model` and `v-model:visible` is supported。Typescript：`boolean` | N
+defaultVisible | Boolean | - | uncontrolled property。Typescript：`boolean` | N
 zIndex | Number | - | \- | N
 onOverlayClick | Function |  | Typescript：`(context: { e: MouseEvent }) => void`<br/>trigger on popup content click | N
 onScroll | Function |  | Typescript：`(context: { e: WheelEvent }) => void`<br/> | N

packages/components/popup/popup.md

@@ -58,6 +58,7 @@ showArrow | Boolean | false | 是否显示浮层箭头 | N
 trigger | String | hover | 触发浮层出现的方式。可选项：hover/click/focus/mousedown/context-menu | N
 triggerElement | String / Slot / Function | - | 触发元素。值类型为字符串表示元素选择器。TS 类型：`string \| TNode`。[通用类型定义](https://github.com/Tencent/tdesign-vue-next/blob/develop/packages/components/common.ts) | N
 visible | Boolean | - | 是否显示浮层。支持语法糖 `v-model` 或 `v-model:visible`。TS 类型：`boolean` | N
+defaultVisible | Boolean | - | 是否显示浮层。非受控属性。TS 类型：`boolean` | N
 zIndex | Number | - | 组件层级，Web 侧样式默认为 5500，移动端和小程序样式默认为 1500 | N
 onOverlayClick | Function |  | TS 类型：`(context: { e: MouseEvent }) => void`<br/>内容面板点击时触发 | N
 onScroll | Function |  | TS 类型：`(context: { e: WheelEvent }) => void`<br/>下拉选项滚动事件 | N