This is especially important for distributions like NixOS where `/bin/bash` doesn't exist, or for MacOS users who've installed a newer version of Bash than the one that comes with their OS.
Signed-off-by: Andrew "Tianon" Page <admwiggin@gmail.com>
Interactive integration testing is useful when you're developing new tests, or
making changes to cli code.
Signed-off-by: Daniel Nephin <dnephin@docker.com>