Add documentation to donation URL feature

[Anavelyz]

Summary

A new feature regarding donation URLs has been added, the documentation is missing. This should be included in the guide.

Documentation Page Link

https://github.com/osl-incubator/scicookie/blob/main/docs/guide.md

Code of Conduct

• I agree to follow the Code of Conduct

[ayxsh678]

Hi, I’d like to work on this. Could you guide me on expected documentation structure?

[Deeksha-indomite]

Hi! I'd like to work on this issue. I'm a Robotics & AI student passionate about open source and this looks like a great first contribution to SciCookie. Could a maintainer please assign it to me?

[xmnlab]

thank you @Deeksha-indomite
appreciate it

[Deeksha-indomite]

thank you @Deeksha-indomite
appreciate it

Thank you! Starting on it now