Updated jest v27 instructions to v28 (testing-library#1061)

Author: abel-rm-rf

docs/react-testing-library/setup.mdx

@@ -285,11 +285,34 @@ using Create React App without TypeScript, save this to `jsconfig.json` instead.
 }
 ```
 
+### Jest 28
+
+If you're using Jest 28 or later, jest-environment-jsdom package now must be installed separately. 
+```
+npm install --save-dev jest-environment-jsdom
+```
+ 
+`jsdom` is also no longer the default environment. You can enable `jsdom` globally by editing `jest.config.js`:
+
+```diff title="jest.config.js"
+ module.exports = {
++ testEnvironment: 'jsdom',
+ // ... other options ...
+ }
+```
+
+Or if you only need `jsdom` in some of your tests, you can enable it as and when needed using
+[docblocks](https://jestjs.io/docs/configuration#testenvironment-string):
+
+```js
+/**
+ * @jest-environment jsdom
+ */
+```
+
 ### Jest 27
 
-If you're using a recent version of Jest (27 or later), `jsdom` is no longer the
-default environment. You can enable `jsdom` globally by editing
-`jest.config.js`:
+If you're using a recent version of Jest (27), `jsdom` is no longer the default environment. You can enable `jsdom` globally by editing `jest.config.js`:
 
 ```diff title="jest.config.js"
  module.exports = {