Fix small typo in README.md

[jameynakama]

Describe the changes you have made:

Just a small typo fix in the README

Reference any relevant issues (e.g. "Fixes #000"):

Pre-Submission Checklist (optional but appreciated):

• [x] I have included relevant documentation updates (stored in /docs)
• [x] I have read docs/CONTRIBUTING.md
• [x] I have read docs/ROADMAP.md

OS Tests (optional but appreciated):

• [ ] Tested on Windows
• [x] Tested on MacOS
• [ ] Tested on Linux