docs: don't install @testing-library/dom

Author: nickserv

docs/react-testing-library/migrate-from-enzyme.mdx

@@ -297,7 +297,7 @@ resemble the way your software is actually used.
 To use the `@testing-library/user-event` module, first install it:
 
 ```bash npm2yarn
-npm install --save-dev @testing-library/user-event @testing-library/dom
+npm install --save-dev @testing-library/user-event
 ```
 
 Now you can import it into your test: