Summary: Typo in `Podfile` comment Unnecessary `\` in iOS Setup code ## Changelog Fixed typos in react-native set up page. Pull Request resolved: https://github.com/facebook/flipper/pull/612 Test Plan: Just Documentation Differential Revision: D18223575 Pulled By: passy fbshipit-source-id: 12c35b4570287d6899769eb0283fb8149fedbeac