Update README.md

Author: ObliviousHarmony

README.md

@@ -18,6 +18,7 @@ If you are not a developer, please use the [WooCommerce plugin page](https://wor
 * [WooCommerce Developer Documentation](https://github.com/woocommerce/woocommerce/wiki)
 * [WooCommerce Code Reference](https://docs.woocommerce.com/wc-apidocs/)
 * [WooCommerce REST API Docs](https://woocommerce.github.io/woocommerce-rest-api-docs/)
+* [Setting up a development environment](https://github.com/woocommerce/woocommerce/wiki/How-to-set-up-WooCommerce-development-environment)
 
 ## Reporting Security Issues
 To disclose a security issue to our team, [please submit a report via HackerOne here](https://hackerone.com/automattic/).