Fix typo in the README.

[mbaitelman]

Fix typo in the README.

Obvious fix.

Description

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Issues Resolved

List any existing issues this PR resolves

Check List

• [ ] All tests pass. See TESTING.md for details.
• [ ] New functionality includes testing.
• [ ] New functionality has been documented in the README if applicable.

[mbaitelman]

The failing checks are for files that were not part of this change. If they need to be fixed before this can be merged I will look into them

[tas50]

Thanks @mbaitelman