Install ansible.posix.debug stdout callback plugin

ansible.builtin.debug is redirected to ansible.posix.debug.
We need to install the collection explicitly.

This needs to be fixed for stdout callback plugin related changes
in ansible-runner >=2.2.0.

Also, increases ansible verbosity to track these issues better in
the future.

Closes-Bug: #1971703
Change-Id: Ibe883e19c25926ab302db741afae70821209a350
(cherry picked from commit 0da3db3b94)

tox.ini

@@ -109,6 +109,7 @@ deps =
 whitelist_externals =
     bash
 commands_pre =
+    ansible-galaxy collection install ansible.posix
     pip install -q bindep fixtures
     bindep test
 commands =

tripleo_heat_templates/tests/test_tht_ansible_syntax.py

@@ -57,7 +57,8 @@ def test_tht_ansible_syntax(pytestconfig):
 
     run = ansible_runner.run(
         playbook=play_path,
-        extravars={'tht_root': tht_root}
+        extravars={'tht_root': tht_root},
+        verbosity=3
     )
 
     try: