Fix typo in README.md

[yizhang24]

Description

This PR is best categorized by the following descriptors:

• Bugfix
• Refactor
• New Feature
• Testing
• Cleanup/Documentation

Context

Spelling error present in README.md

Closes [None]

What Has Changed?

Spelling error has been fixed.

No breaking changes.

Checklists

Testing

• This PR has been tested/verified during a meeting with no issues found.
• This PR has been tested/verified during driver practice with no issues found.
• This PR has been tested/verified at competition with no issues found.

Formatting

• This PR passes auto-formatting checks.
• The code introduced in this PR is self-documenting through reasonable variable and function names.

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• This PR is ready to merge. Sufficient reasoning has been given for any
  points left unchecked above.