Fix developer guide link in README.md (#859)

Closes: #...

## Checklist

- [ ] I have written tests
- [ ] I have provided documentation

## Changelog

- A bullet list of what you've done to make the life of the reviewer
easier.

## How to test

A consise description of how to test the newly implemented
functionality.

README.md

@@ -5,7 +5,7 @@ applications that power the Online web experience.
 
 ## Contributing
 
-Please see the [developer guide](docs/developer-guide.md) for information on how to get started with development.
+Please see the [developer guide](CONTRIBUTING.md) for information on how to get started with development.
 
 <a href="https://vercel.com?utm_source=[team-name]&utm_campaign=oss" width="150" height="30">
     <img src="https://images.ctfassets.net/e5382hct74si/78Olo8EZRdUlcDUFQvnzG7/fa4cdb6dc04c40fceac194134788a0e2/1618983297-powered-by-vercel.svg" alt="Vercel">