Fix tempest source install condition

Because of jinja2 templating delimiters inside when statement tempest
wasn't correctly installed from source.
Also condition is simplified to be more readable. install_method check
works as we would like to run venv installation only for source
installs, but not for the ubuntu mixed setup.

Depends-On: https://review.opendev.org/686041
Change-Id: I39332a35fb2edae65a4762fe24c5b1f8c8675a2b

tasks/tempest_install_source.yml

@@ -29,11 +29,7 @@
       - section: "tempest"
         option: "venv_tag"
         value: "{{ tempest_venv_tag }}"
-  # Note(jrosser) this task can be conditional on tempest_plugin_install_source
-  # but then that variable must be in scope when the handler inside python_venv_build
-  # runs, so it is better to duplicate the underlying condition logic
-  # when: not tempest_plugin_install_source
-  when: not "{{ ((tempest_install_method | default('source') == 'distro') and (ansible_os_family | lower == 'debian')) | bool }}"
+  when: tempest_install_method | default('source') == 'source'
 
 - name: Get tempest plugins from git
   git:

templates/tempest.conf.j2

@@ -67,7 +67,8 @@ admin_role = admin
 
 
 [identity-feature-enabled]
-trust = false
+trust = true
+application_credentials = true
 
 
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