Add Developer Ecosystem to websites (#3540)

Author: durkinio

README.md

@@ -131,6 +131,7 @@ Websites built with Gatsby:
 * [manu.ninja](https://manu.ninja/) ([source](https://github.com/Lorti/manu.ninja))
 * [Kris Hedstrom's Portfolio](https://k-create.com/) ([source](https://github.com/kristofferh/kristoffer))
 * [Chocolate free website](https://chocolate-free.com/) ([source](https://github.com/Khaledgarbaya/chocolate-free-website))
+* [Developer Ecosystem](https://www.developerecosystem.com/) 
 
 ## Docs