Update README.md

[SylviaDu99]

Fixes #276
Fixes #244

[MaxGhenis]

Please drop 3.9 support while you're here: #244

Edit the initial description to link both issues: https://docs.github.com/en/issues/tracking-your-work-with-issues/using-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword

[SylviaDu99]

Hello @MaxGhenis, thank you for your comment. I want to make sure that I fully get what you meant since only changing the prerequisites in README.md does not solve issue #244. I believe we will be solving issue #244 when working on my other PR #267.

[MaxGhenis]

Please fix #244 here, as #267 will take more time. It should be straightforward.

[MaxGhenis]

Please link and close the two issues. For next time, following the instructions in my previous comment will do this automatically.