Clone older tempestconf if py3 is not available

If py3 is not available, let's clone latest python-tempestconf
which supports py2 - 2.5.0 version. Otherwise the role won't be
able to generate tempest.conf required for refstack-client as
python-tempestconf will fail because the by default cloned version
is py3 only.

Change-Id: I25a0dc99fb7cba3163b90f1678ae2dcb65e66a7f

tasks/install-refstack-client.yaml

@@ -25,6 +25,15 @@
     python3_param: "-p 3"
   when: python3_is_available.rc == 0
 
+- name: Clone py2 python-tempestconf
+  git:
+    repo: 'https://git.openstack.org/osf/python-tempestconf.git'
+    dest: "{{ refstack_client_source }}/.tempestconf_source"
+    version: "2.5.0"
+  when:
+    - python3_is_available.rc != 0
+    - tempestconf_source is not defined
+
 - when: refstack_tempest_plugins is defined
   block:
     # refstack-client allows installation of additional packages to find more
@@ -55,6 +64,9 @@
     {% if tempestconf_source is defined %}
       -s {{ tempestconf_source }}
     {% endif %}
+    {% if tempestconf_source is not defined and python3_is_available.rc != 0 %}
+      -s {{ refstack_client_source }}/.tempestconf_source
+    {% endif %}
   args:
     chdir: "{{ refstack_client_source }}"
   changed_when: true