Onboarding page from community guide

[sanketverma1704]

Hi all.

While working on #246, I realised that the onboarding page is incomplete. After discussing with @juanis2112, we've decided to remove the page for now. I'm copy pasting the content here if we/someone plans to work on it later on.

- Organizing sprints
  - Organising sprints are an excellent way to invite new collaborators, solve issues, gather contributions and broaden the project community. Some helpful tips for organising a sprint efficiently:
    - Have a list of issues from the issue tracker that can be worked on. The issues should have a mix of code (bugs, features, fixes) and no-code (documentation) tasks so that they can accommodate a diverse set of participants
- Handling a storm of new contributors during peak season (GSoC, Outreachy, GSOD etc.)

Thanks!