chore: cleanup legacy extend-expect from code and docs (#1739)

Author: mdjastrzebski

examples/react-navigation/.gitignore

@@ -1,5 +1,4 @@
 import { resetToDefaults, configure } from './src/pure';
-import './src/matchers/extend-expect';
 
 beforeEach(() => {
   resetToDefaults();

examples/react-navigation/README.md

@@ -1,4 +1,3 @@
-import '../../matchers/extend-expect';
 import * as React from 'react';
 import { TextInput, View } from 'react-native';
 import { fireEvent, render, screen } from '../..';

examples/react-navigation/babel.config.js

@@ -4,20 +4,7 @@ This guide describes built-in Jest matchers, we recommend using these matchers a
 
 ## Setup
 
-You can use the built-in matchers by adding the following line to your `jest-setup.ts` file (configured using [`setupFilesAfterEnv`](https://jestjs.io/docs/configuration#setupfilesafterenv-array)):
-
-```ts title=jest-setup.ts
-import '@testing-library/react-native/extend-expect';
-```
-
-Alternatively, you can add above script to your Jest configuration (usually located either in the `jest.config.js` file or in the `package.json` file under the `"jest"` key):
-
-```json title=jest.config.js
-{
-  "preset": "react-native",
-  "setupFilesAfterEnv": ["@testing-library/react-native/extend-expect"]
-}
-```
+There is no need to set up the built-in matchers; they are automatically available in your tests when you import anything from `@testing-library/react-native`, e.g., `render`.
 
 ## Migration from legacy Jest Native matchers.
 

examples/react-navigation/jest-setup.js

@@ -8,7 +8,7 @@ All of the built-in Jest matchers provided by the React Native Testing Library s
 
 ## Usage
 
-You don't need to do anything to use the built-in matchers. They are automatically available when you import anything from `@testing-library/react-native`.
+There is no need to set up the built-in matchers; they are automatically available in your tests when you import anything from `@testing-library/react-native`, e.g., `render`.
 
 ### Gradual migration