Upgrade dotenv-expand to 4.2.0 in 1.x branch#4000

Merged

gaearon merged 1 commit intofacebook:masterfrom iansu:dotenv-expand-backport

Feb 9, 2018

+1-1

Commits on Feb 9, 2018

Update dotenv-expand to fix bug with environment variables that contain a $.
iansu
committed