chore: update README

[calebpollman]

Description of changes

Update code block language in README

Issue #, if available

Description of how you validated changes

Checklist

• [ ] PR description included
• [ ] yarn test passes
• [ ] Tests are [changed or added]
• [ ] Relevant documentation is changed or added (and PR referenced)

[github-actions[bot]]

:tada: This PR is included in version 3.0.0-unstable.14 :tada:

The release is available on:

• npm package (@unstable dist-tag)
• GitHub release

Your semantic-release bot :package::rocket:

[github-actions[bot]]

:tada: This PR is included in version 4.0.1 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: