[Docs] Update website/community/mailing-lists.md

[krishna-dave206]

Description

Mailing lists file needs to updated.

Location of the Issue

website/community/mailing-lists.md

[krishna-dave206]

@andrewmusselman @rawkintrevo Have a look at this.

[Rutuja123-dos]

Hi, I’m a 2nd year Computer Engineering student and new to Apache Mahout. I’d like to work on this issue. Please let me know if I can proceed. And I am also new to open source