Summary:
[Folly upgrade](a70625abd7) introduced changes that have to be applied to `Install Third Party` script in order to use `New build system` from Xcode 10. Unfortunately, this might happen again if someone changes folly. Also removes non-existent files from folly podspec.
Pull Request resolved: https://github.com/facebook/react-native/pull/22394
Differential Revision: D13192463
Pulled By: hramos
fbshipit-source-id: ea0eeb6e1e7f6d7dfcdb6d1dee28b1a640ee7097
287934dba9