You can automate it by using this guide.
https://github.com/ahwayakchih/openshift-nodebb
Or the one written by me.
https://community.nodebb.org/topic/3866/guide-nodebb-0-6-1-on-openshift-for-windows-users-with-putty/1
Or use official NodeBB guide.
https://github.com/NodeBB/nodebb-english/blob/master/installing/cloud/openshift.rst
This is not a bug. You have used npm install command in the wrong folder. Use OpenShift Online in your browser to download NodeBB files to /app-root/runtime/repo and it will work as it should.