Update MAINTAINERS.md (#86)

Add Evan David to list of project maintainers.

Author: evandavid1

MAINTAINERS.md

@@ -24,6 +24,7 @@
 |-----------------|------------------------------------------------------------|------------------------|-----------------------------------------|
 | Olaoluwa Ademola Salami * | [olaoluwasalami](https://github.com/olaoluwasalami)  | DevOps Engineer        |                                          |
 | Rajan Chari *    | [rajan-chari](https://github.com/rajan-chari)                | Microsoft Research                | CAP                        |
+| Evan David *    | [evandavid1](https://github.com/evandavid1)                | -                      | gpt assistant, group chat, rag, autobuild |
 
 ## I would like to join this list. How can I help the project?
 > We're always looking for new contributors to join our team and help improve the project. For more information, please refer to our [CONTRIBUTING](https://autogenhub.github.io/autogen/docs/contributor-guide/contributing) guide.