Update NodeJS source for Docker Image (#11707)

* Update Ruby/Node/jemalloc source for Docker Image

* Update Dockerfile

* Update Dockerfile

Dockerfile

@@ -4,7 +4,7 @@ FROM ubuntu:18.04 as build-dep
 SHELL ["bash", "-c"]
 
 # Install Node
-ENV NODE_VER="8.15.0"
+ENV NODE_VER="12.9.1"
 RUN	echo "Etc/UTC" > /etc/localtime && \
 	apt update && \
 	apt -y install wget make gcc g++ python && \