Documentation📄: Improve the `Join the moja global` section

What is the current documentation state?

Currently, the concerned documentation piece lacks some of the information and context around the new areas that we are working on. We would ideally like to improve this section for better communication and onboard new contributors with confidence,

Where is this stated?

https://docs.moja.global/en/latest/contact.html

Why do you want to improve the statement?

No response

Proposed Statement

The following changes should be implemented:

• Change the URL slug from contact to join-moja-global
• Add Outreachy Internship to Outreach and Student Programs.
• Add Community Website to moja global outreach.
• Add a section about Documentation Working Groups by picking some content here.
• Add the Slack invitation link: https://www.google.com/url?q=https://join.slack.com/t/mojaglobal/shared_invite/zt-o6ta1ug0-rVLjAo460~d7JbZ~HpFFtw&sa=D&source=editors&ust=1633078795555000&usg=AFQjCNFbieFLALt9IFd9pqxYz1S54wj-Rg

Additional context.

No response