Set the GOROOT and GOPATH env variables in Dockerfile

Author: ccojocar

Dockerfile

@@ -1,6 +1,8 @@
 FROM golang:1.10.3-alpine3.8
 
 ENV BIN=gosec
+ENV GOROOT=/usr/local/go
+ENV GOPATH=/go
 
 COPY $BIN /go/bin/$BIN
 COPY docker-entrypoint.sh /usr/local/bin