Update content of README.sw.md

[Famaskah]

Hi there,

I am Famaskah, a university student from Tanzania.

I would like to update the README.sw.md file to improve its content and ensure it stays up-to-date.

Please let me know if this is okay. Thank you!

[rammba]

Hello @Famaskah, thanks for raising this issue.
We're always happy to introduce new languages and improve existing ones. Feel free to add the changes and open pull request when you're done.
Same goes for #111583.