exact prop isn't needed in React Router v6

Fixes #4728

docs/tutorials/essentials/part-6-performance-normalization.md

@@ -137,11 +137,11 @@ As we've seen before, we can take data from one `useSelector` call, or from prop
 As usual, we will add routes for these components in `<App>`:
 
 ```tsx title="App.tsx"
- <Route exact path="/posts/:postId" component={SinglePostPage} />
- <Route exact path="/editPost/:postId" component={EditPostForm} />
+ <Route path="/posts/:postId" component={SinglePostPage} />
+ <Route path="/editPost/:postId" component={EditPostForm} />
  // highlight-start
- <Route exact path="/users" component={UsersList} />
- <Route exact path="/users/:userId" component={UserPage} />
+ <Route path="/users" component={UsersList} />
+ <Route path="/users/:userId" component={UserPage} />
  // highlight-end
  <Redirect to="/" />
 ```