Add a ptest to the developer role

[bmbouter]

As a developer I am always trying to run the tests, but I always have to go look in the CI to remember the commands to do it.

For the functional tests it's usually something like:

    pytest -v -r sx --color=yes --suppress-no-test-exit-code --pyargs pulp_ansible.tests.functional -m parallel -n 8
    pytest -v -r sx --color=yes --pyargs pulp_ansible.tests.functional -m "not parallel"

It would be great to have a ptest pulp_ansible that produces these ^ commands. Later we can also add the unit tests, but the way those are getting invoked is changing so let's just do the functional tests for now.