fix: unmount takes no argument since vue-next v3.0.6

Author: cexbrayat

src/vueWrapper.ts

@@ -234,7 +234,7 @@ export class VueWrapper<T extends ComponentPublicInstance>
       )
     }
 
-    this.__app.unmount(this.parentElement)
+    this.__app.unmount()
   }
 }