fix: vue2 onMounted bug

Author: zuofenghua

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ahooks-vue",
-  "version": "0.12.1",
+  "version": "0.12.2",
   "description": "ahooks-vue",
   "types": "dist/src/index.d.ts",
   "repository": "https://github.com/dewfall123/ahooks-vue.git",

src/utils/lifeCircle.ts

@@ -2,7 +2,7 @@ import { getCurrentInstance, onMounted } from 'vue-demi';
 
 export function safeOnMounted(hook: () => any) {
   const instance = getCurrentInstance();
-  if (instance?.isMounted) {
+  if (instance?.isMounted || (instance as any)._isMounted) {
     hook();
   } else {
     onMounted(hook);