Update fork-ts-checker-webpack-plugin out of alpha (#6739)
Update fork-ts-checker-webpack-plugin out of alpha (#6739)

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ConnectedHomes/create-react-web-app,ConnectedHomes/create-react-web-app,jdcrensh/create-react-app,GreenGremlin/create-react-app,GreenGremlin/create-react-app,ConnectedHomes/create-react-web-app,d3ce1t/create-react-app,ConnectedHomes/create-react-web-app,Timer/create-react-app,jdcrensh/create-react-app,d3ce1t/create-react-app,GreenGremlin/create-react-app,facebookincubator/create-react-app,GreenGremlin/create-react-app,Timer/create-react-app,facebookincubator/create-react-app,d3ce1t/create-react-app,jdcrensh/create-react-app,Timer/create-react-app,jdcrensh/create-react-app,d3ce1t/create-react-app,Timer/create-react-app,facebookincubator/create-react-app