docs: import missing DOMWrapper on Implementation of the plugin secti…

…on (#2519)

Co-authored-by: Brendon Silva <[email protected]>

docs/guide/extending-vtu/plugins.md

@@ -103,7 +103,7 @@ wrapper.findByTestId('name-input') // returns a VueWrapper or DOMWrapper
 Implementation of the plugin:
 
 ```js
-import { config } from '@vue/test-utils'
+import { config, DOMWrapper} from '@vue/test-utils'
 
 const DataTestIdPlugin = (wrapper) => {
   function findByTestId(selector) {