test_with_docker: shorter var names
test_with_docker: shorter var names

No need to add type suffixes to variables, unless dealing with the
same data represented by different types in the same method.

Prefer single-letter or very short var names when usage is immediate
and obvious, this aids readability. For tiny functions like this,
where usage cannot be far away, one-letter is a very reasonable default.

nyarly/sous,samsalisbury/sous,nyarly/sous,opentable/sous,samsalisbury/sous,samsalisbury/sous,opentable/sous,opentable/sous,opentable/sous,samsalisbury/sous,nyarly/sous,opentable/sous,samsalisbury/sous