Rework using
https://pagure.io/modularity-testing-framework/blob/master/f/moduleframework/module_framework.py#_153 to allow using commands like:

self.run("su - usertest -c 'touch ~/testfile.txt'")
actually it tracebacks,
should work with ' and also with "

self.run should be called like:

cat << EOF |  docker exec -i aaa bash
> adduser test
> su test -c "ls -alh ~"
> su test -c 'ls -alh ~'
> EOF

it has to be fifed in both helpers: also here: https://pagure.io/modularity-testing-framework/blob/master/f/moduleframework/module_framework.py#_220