Update the publishing guide - Add the steps to update the readme with the latest version

[helio-frota]

Here is showing 10.1.0 | (10.x)
https://hub.docker.com/r/bucharestgold/centos7-s2i-nodejs/
And the last published is 10.4.0
When following the guide: https://github.com/bucharest-gold/centos7-s2i-nodejs/blob/master/PUBLISHING.md is easy to forget to update the Readme.