[CORD-1184] Moving node image to 7.9.0

Change-Id: Ibc13feabfed713dd85a7618447402d57a05e9215
(cherry picked from commit ea334d5ebb3c3e091dc1f8c956d5c28e986532fe)
diff --git a/Dockerfile b/Dockerfile
index a2becfb..7663336 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,7 +2,7 @@
 # To build use: docker build -t xosproject/xos-ws .
 # To run use: docker run -p 3000:3000 -d xosproject/xos-ws
 
-FROM node:argon
+FROM node:7.9.0
 
 # Set environment variables
 ENV CODE_SOURCE .