docs: adds a code coverage badge to the README

[thawkin3]

I've added a code coverage badge from Codecov to the README. This repo has 97% code coverage through the Jest unit tests, so we may as well flaunt it. Behold!

PR Checklist

Please leave this checklist in your PR.

• Issue being fixed is referenced.
• Source changes maintain:
  • Stated browser compatibility.
  • Stated React compatibility.
• Unit test coverage added/updated.
• E2E test coverage added/updated.
• Prop-types added/updated.
• Typings added/updated.
• README updated (API changes, instructions, etc.).
• Changes to dependencies explained.
• Changeset added (run yarn changeset locally to add one, and follow the prompts).
  • EXCEPTION: A Changeset is not required if the change does not affect any of the source files that produce the package bundle. For example, tooling changes, test updates, or a new dev-only dependency to run tests more efficiently should not have a Changeset since it will not affect package consumers.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 46bb7f2

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[codecov]

Codecov Report

Merging #233 (46bb7f2) into master (9d11b09) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #233   +/-   ##
=======================================
  Coverage   97.14%   97.14%           
=======================================
  Files           1        1           
  Lines          70       70           
  Branches       26       26           
=======================================
  Hits           68       68           
  Misses          2        2           

---

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[thawkin3]

Thanks for merging this so quickly!

[thawkin3]

@all-contributors please add @thawkin3 for docs

[allcontributors]

@thawkin3

I've put up a pull request to add @thawkin3! 🎉

[stefcameron]

@thawkin3 Thanks for adding the badge! For sure, we should highlight that. I forgot the badge when I integrated the bot.