Fix typo in `DirectionalHint` Callout type

[lawrencewin]

Platforms Impacted

• [ ] iOS
• [x] macOS
• [x] win32 (Office)
• [ ] windows
• [ ] android

Description of changes

There's a typo in the DirectionalHint type for Callout's directionalHint prop, where "bottomLeftEdge" is spelled as "bottonLeftEdge". This PR fixes this so the linter stops spitting an incorrect error.

Pull request checklist

This PR has considered (when applicable):

• [ ] Automated Tests
• [ ] Documentation and examples
• [ ] Keyboard Accessibility
• [ ] Voiceover
• [ ] Internationalization and Right-to-left Layouts

[Saadnajmi]

Which.. after that, we'll have to ensure that the change makes it internally and doesn't cause regressions for partners who don't update their bundles..

[PPatBoyd]

Which.. after that, we'll have to ensure that the change makes it internally and doesn't cause regressions for partners who don't update their bundles..

FWIW there are no current users of the enum value that I could find in any Office repos