docs: prefer shorter demo

src/contact-edit/README.md

@@ -32,13 +32,8 @@ import { Toast } from 'vant';
 export default {
   setup() {
     const editingContact = ref({});
-    const onSave = (contactInfo) => {
-      Toast('Save');
-    };
-    const onDelete = (contactInfo) => {
-      Toast('Delete');
-    };
-
+    const onSave = (contactInfo) => Toast('Save');
+    const onDelete = (contactInfo) => Toast('Delete');
     return {
       onSave,
       onDelete,

src/contact-edit/README.zh-CN.md

@@ -36,13 +36,8 @@ import { Toast } from 'vant';
 export default {
   setup() {
     const editingContact = ref({});
-    const onSave = (contactInfo) => {
-      Toast('保存');
-    };
-    const onDelete = (contactInfo) => {
-      Toast('删除');
-    };
-
+    const onSave = (contactInfo) => Toast('保存');
+    const onDelete = (contactInfo) => Toast('删除');
     return {
       onSave,
       onDelete,

src/contact-edit/demo/index.vue

@@ -30,12 +30,8 @@ export default {
     const t = useTranslate(i18n);
     const editingContact = ref({});
 
-    const onSave = () => {
-      Toast(t('save'));
-    };
-    const onDelete = () => {
-      Toast(t('delete'));
-    };
+    const onSave = () => Toast(t('save'));
+    const onDelete = () => Toast(t('delete'));
 
     return {
       t,