[Docs] GitHub Organization Setup Docs

[JRS296]

Docs Page: https://github.com/Dijkstra-Edu/Docs
Current Preview: https://docs.dijkstra.org.in/

Task - Need you to document how to Join Dijkstra's GitHub Organization (with Screenshots)
For this, i need you to leave, and come back again through the same process

[JRS296]

@Prababil Is this task completed? If so can you update this?