tripleo-ansible module jobs are not testing the proposed change for some roles

We set ANSIBLE_LIBRARY in the molecule test execution, however this value is appended to a generated list that includes the system /usr/share/ansible/modules path. If you install tripleo-ansible the package, any changes won't actually test the code being proposed but rather that packaged module.

Related molecule change: https://github.com/ansible-community/molecule/commit/17c5da0e831a36f226769029d6452d8d0d692fd7

This was found when https://review.opendev.org/c/openstack/tripleo-ansible/+/780966 failed on the molecule test saying it couldn't find the parameter being added.