macOS : request interactive input when killing the packager (#19663)
macOS : request interactive input when killing the packager (#19663)

Summary:
Do not request interactive input when running on a CI

When I'm running the build on my CI server, many Terminal windows are remaining on the server because of the `read` command.

This PR prevent this behaviour when the `CI` environment variable is defined so that it doesn't alter the behaviour on local machines.
Pull Request resolved: https://github.com/facebook/react-native/pull/19663

Differential Revision: D14206458

Pulled By: cpojer

fbshipit-source-id: 476067ebebb07c6e708469fa8829a06e05c58200

hoangpham95/react-native,hoangpham95/react-native,exponentjs/react-native,myntra/react-native,myntra/react-native,exponentjs/react-native,exponent/react-native,exponent/react-native,javache/react-native,javache/react-native,myntra/react-native,exponent/react-native,pandiaraj44/react-native,janicduplessis/react-native,facebook/react-native,facebook/react-native,pandiaraj44/react-native,hoangpham95/react-native,exponentjs/react-native,facebook/react-native,hammerandchisel/react-native,hammerandchisel/react-native,facebook/react-native,exponentjs/react-native,myntra/react-native,janicduplessis/react-native,pandiaraj44/react-native,hammerandchisel/react-native,myntra/react-native,hammerandchisel/react-native,exponent/react-native,hammerandchisel/react-native,javache/react-native,javache/react-native,myntra/react-native,exponent/react-native,pandiaraj44/react-native,exponentjs/react-native,hammerandchisel/react-native,arthuralee/react-native,pandiaraj44/react-native,hammerandchisel/react-native,hoangpham95/react-native,facebook/react-native,javache/react-native,myntra/react-native,arthuralee/react-native,janicduplessis/react-native,arthuralee/react-native,exponentjs/react-native,janicduplessis/react-native,arthuralee/react-native,exponent/react-native,facebook/react-native,facebook/react-native,exponentjs/react-native,hammerandchisel/react-native,hoangpham95/react-native,hoangpham95/react-native,facebook/react-native,pandiaraj44/react-native,facebook/react-native,exponent/react-native,javache/react-native,myntra/react-native,javache/react-native,janicduplessis/react-native,exponent/react-native,hoangpham95/react-native,myntra/react-native,janicduplessis/react-native,javache/react-native,pandiaraj44/react-native,exponentjs/react-native,hoangpham95/react-native,javache/react-native,janicduplessis/react-native,pandiaraj44/react-native,arthuralee/react-native,janicduplessis/react-native