message: docs(Popover): use composition api
diff: @@ -23,23 +23,27 @@ app.use(Popover);
  ```
  ```js
  +import { ref } from 'vue';
  import { Toast } from 'vant';
  export default {
  - data() {
  - return {
  - showPopover: false,
  - actions: [
  + setup() {
  + const showPopover = ref(false);
  + const actions = [
  { text: 'Option 1' },
  { text: 'Option 2' },
  { text: 'Option 3' },
  - ],
  - };
  - },
  - methods: {
  - onSelect(action) {
  + ];
  +
  + const onSelect = (action) => {
  Toast(action.text);
  - },
  + };
  +
  + return {
  + actions,
  + onSelect,
  + showPopover,
  + };
  },
  };
  ```
  @@ -57,15 +61,20 @@ Using the `theme` prop to change the style of Popover.
  ```
  ```js
  +import { ref } from 'vue';
  +
  export default {
  - data() {
  - return {
  - showPopover: false,
  - actions: [
  + setup() {
  + const showPopover = ref(false);
  + const actions = [
  { text: 'Option 1' },
  { text: 'Option 2' },
  { text: 'Option 3' },
  - ],
  + ];
  +
  + return {
  + actions,
  + showPopover,
  };
  },
  };
  @@ -105,15 +114,20 @@ bottom-end # Bottom right
  ```
  ```js
  +import { ref } from 'vue';
  +
  export default {
  - data() {
  - return {
  - showPopover: false,
  - actions: [
  + setup() {
  + const showPopover = ref(false);
  + const actions = [
  { text: 'Option 1', icon: 'add-o' },
  { text: 'Option 2', icon: 'music-o' },
  { text: 'Option 3', icon: 'more-o' },
  - ],
  + ];
  +
  + return {
  + actions,
  + showPopover,
  };
  },
  };
  @@ -132,15 +146,20 @@ Using the `disabled` option to disable an action.
  ```
  ```js
  +import { ref } from 'vue';
  +
  export default {
  - data() {
  - return {
  - showPopover: false,
  - actions: [
  + setup() {
  + const showPopover = ref(false);
  + const actions = [
  { text: 'Option 1', disabled: true },
  { text: 'Option 2', disabled: true },
  { text: 'Option 3' },
  - ],
  + ];
  +
  + return {
  + actions,
  + showPopover,
  };
  },
  };
  @@ -172,11 +191,12 @@ export default {
  ```
  ```js
  +import { ref } from 'vue';
  +
  export default {
  - data() {
  - return {
  - showPopover: false,
  - };
  + setup() {
  + const showPopover = ref(false);
  + return { showPopover };
  },
  };
  ```
  