Update healthcheck to 5s timeout

Dockerfile

@@ -50,4 +50,4 @@ CMD [ "yarn", "start" ]
 EXPOSE ${PORT}
 
 # Run simple healthchecks every 5 mins, to check that everythings still great
-HEALTHCHECK --interval=5m --timeout=2s --start-period=30s CMD yarn health-check
+HEALTHCHECK --interval=5m --timeout=5s --start-period=30s CMD yarn health-check