Update README testing section

[aamarill]

Issue #440 has been resolved, so this line can be removed?

Make sure these boxes are checked before your pull request (PR) is ready to be reviewed and merged. Thanks!

• tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR -- or run tests locally with rake test
• code is in uniquely-named feature branch and has no merge conflicts
• PR is descriptively titled
• PR body includes fixes #0000-style reference to original issue #
• ask @publiclab/reviewers for help, in a comment below

[aamarill]

@publiclab/reviewers I do apologize if I was supposed to make this an issue before submitting a PR. But it's a short enough PR that I though it would be appropriate 😄

[PublicLabBot]

	2 Messages
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[SidharthBansal]

Thanks @aamarill for contributing at public lab. Yeah, the link is obsolete now.

@jywarren can you please merge this one?

[SidharthBansal]

Well done

[aamarill]

🙏 Thank you 🙌

[jywarren]

Hooray!!!! 🎉 🎊 🕺