feat(resources): add 'Approachable Open Source' in books resources (#…

…1012)

Co-authored-by: Julien Déramond <juderamond@gmail.com>

src/content/docs/resources/books.mdx

@@ -15,6 +15,7 @@ import banner from '../../../assets/resources/books.png';
 
 Find our recommended books related to open source:
 
+- [Approachable Open Source](https://approachableopensource.com/) by Brian Muenzenmeyer
 - [Producing Open-Source Software](https://producingoss.com/) by Karl Fogel
 - [Uncurled](https://un.curl.dev) by Daniel Stenberg
 - [Working in Public: The Making and Maintenance of Open-Source Software](https://www.amazon.com/Working-Public-Making-Maintenance-Software/dp/0578675862) by Nadia Eghbal