need to specify strategy plugin for ansible ad-hoc

.ci/debops_common_tests.py

@@ -26,12 +26,14 @@ with ci_lib.Fold('job_setup'):
     ci_lib.run('debops-init %s', project_dir)
     os.chdir(project_dir)
 
+    ansible_strategy_plugin = "{}/ansible_mitogen/plugins/strategy".format(ci_lib.GIT_ROOT)
+
     with open('.debops.cfg', 'w') as fp:
         fp.write(
             "[ansible defaults]\n"
-            "strategy_plugins = %s/ansible_mitogen/plugins/strategy\n"
+            "strategy_plugins = {}\n"
             "strategy = mitogen_linear\n"
-            % (ci_lib.GIT_ROOT,)
+            .format(ansible_strategy_plugin)
         )
 
     with open(vars_path, 'w') as fp:
@@ -65,7 +67,8 @@ with ci_lib.Fold('job_setup'):
     print()
 
     print("Setting up python-netaddr...")
-    ci_lib.run('ansible all -i {} -m apt -a "name=python-netaddr state=present" --become'.format(inventory_path))
+    ci_lib.run('ANSIBLE_STRATEGY_PLUGINS={} ansible all -i {} -m apt -a "name=python-netaddr state=present" --become'.format(
+        ansible_strategy_plugin, inventory_path))
 
     # Now we have real host key checking, we need to turn it off
     os.environ['ANSIBLE_HOST_KEY_CHECKING'] = 'False'