Add step for fetching backers.json to website install steps

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ### Features
 
+- `[docs]` Add step for fetching `backers.json` file in website setup docs ([#10631](https://github.com/facebook/jest/pull/10631))
 - `[jest-cli, jest-config]` Add support for the `jest.config.ts` configuration file ([#10564](https://github.com/facebook/jest/pull/10564))
 
 ### Fixes

CONTRIBUTING.md

@@ -143,6 +143,7 @@ If you are making changes to the website or documentation, test the website fold
     ```sh-session
     $ cd website       # Only needed if you are not already in the website directory
     $ yarn
+    $ node fetchSupporters.js
     $ yarn start
     ```
 1.  You can run a development server to check if the changes you made are being displayed accurately by running `yarn start` in the website directory.

website/README.md

@@ -10,6 +10,12 @@ yarn
 
 in the root directory.
 
+Fetch `backers.json` file by running
+
+```bash
+node fetchSupporters.js
+```
+
 Then, run the server via
 
 ```bash