chore: bump Node.js v18 (#11439)

packages/vant/package.json

@@ -51,7 +51,7 @@
     "vue": "^3.0.0"
   },
   "devDependencies": {
-    "@types/node": "^16.11.56",
+    "@types/node": "^18.11.18",
     "@types/jest": "^29.1.1",
     "@vant/area-data": "workspace:*",
     "@vant/cli": "workspace:*",

packages/vant/src/area/utils.ts

@@ -95,7 +95,7 @@ export function formatDataForCascade({
     });
   }
 
-  const options = Array.from(provinceMap.values()) as PickerOption[];
+  const options = Array.from(provinceMap.values());
 
   if (placeholder.length) {
     const county = showCounty ? [makeOption(placeholder[2])] : undefined;