Summary:
Include a default blacklist into the build settings to prevent
processing of incorrect fixture files by Metro.
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Fix#17610 issue, preventing metro from processing fixture files
1. Have a working demo
2. Install https://github.com/oblador/react-native-vector-icons
3. Use in a component
4. Start the app
5. The app starts successfully and display the icons
[ GENERAL ] [ BUGFIX ] [local-cli/util/Config.js] - Add default file blacklist
Closes https://github.com/facebook/react-native/pull/17672
Differential Revision: D7014627
Pulled By: hramos
fbshipit-source-id: 20974e6fdd0977eeeb1048c29c9d621c803c26e9
54dc11a5fb