Summary:
Remove redundant `\`` mark
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- [x] Explain the **motivation** for making this change.
- [x] Provide a **test plan** demonstrating that the code is solid.
- [x] Match the **code formatting** of the rest of the codebase.
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This PR fixes Documentation typo.
No need for test.
Closes https://github.com/facebook/react-native/pull/13228
Differential Revision: D4810457
Pulled By: hramos
fbshipit-source-id: 5c475a5d8b51d4a926e0fc737e2a12805e3bf70b
8e925d578b