[docker] Build with UB 18.04 and go 1.9

Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:16.04
+FROM ubuntu:18.04
 
 ENV DEBIAN_FRONTEND noninteractive
 

docker/build-go.sh

@@ -5,7 +5,7 @@ set -x
 set -e
 
 # Components versions
-export GOLANG_VERSION="1.9"
+export GOLANG_VERSION="1.9.2"
 export GOLANG_SRC_URL="https://golang.org/dl/go$GOLANG_VERSION.src.tar.gz"
 export GOLANG_SRC_SHA256="406865f587b44be7092f206d73fc1de252600b79b3cacc587b74b5ef5c623596"