Fix ansible test runner

The test runner was setting a default flag for the option
`tripleo_job_ansible_args` which was resulting in tests being
executed in convergence mode. When in convergence mode, a given
secnario is expected because the test will run with extra args,
which are assumed to be scenario specific. This change sets the
default for `tripleo_job_ansible_args` to an empty string which
will ensure the test runner is running all discovered scenarios
when envoked.

Change-Id: I7cd7ded239f32eb8fd2a697b1b42154841712fc2
Signed-off-by: Kevin Carter <kecarter@redhat.com>

zuul.d/playbooks/run.yml

@@ -23,7 +23,7 @@
         pytest --color=no \
                --html={{ ansible_user_dir }}/zuul-output/logs/reports.html \
                --self-contained-html \
-               --ansible-args='{{ tripleo_job_ansible_args | default("-v") }}' \
+               --ansible-args='{{ tripleo_job_ansible_args | default('') }}' \
                {{ tripleo_ansible_project_path }}/tests/test_molecule.py
       args:
         chdir: "{{ tripleo_ansible_project_path }}/tripleo_ansible/roles/{{ tripleo_role_name }}"