Avoid `fab_run()` for Jenkins deployment

The `provision` task specifically targets Jenkins platform that can only exist
in local environment. Direct usage of `local()` operation prevents accidental
manipulation of build artifacts in other environments.

deploy.py

@@ -175,27 +175,26 @@ def deploy(environment):
 
 
 @task
-def provision(environment, role='local'):
+def provision(environment):
     """
     Provision a Jenkins deployment.
     This task loads the target environment and extract the archive to deploy.
     :param environment The environment to deploy the site DEV, STAGE, PROD
-    :param role Tha fabric role to run the task.
     """
     _set_hosts(environment)
 
     artefact = _get_archive_from_dir(env.builddir)
 
-    with h.fab_cd(role, '{}/src'.format(env.workspace)):
+    with lcd('{}/src'.format(env.workspace)):
         # Clear the currently installed platform
-        if h.fab_exists(role, env.site_root):
-            h.fab_run(role, 'rm -rf {}'.format(env.site_root))
+        if os.path.exists(env.site_root):
+            local('rm -rf {}'.format(env.site_root))
 
         # Extract the platform to deploy
-        h.fab_run(role, 'tar -xzf {}/{}'.format(env.builddir, artefact))
+        local('tar -xzf {}/{}'.format(env.builddir, artefact))
 
         # Fast-check if the archive looks like a Drupal installation
-        if not h.fab_exists(role, '{}/src/drupal'.format(env.workspace)):
+        if not os.path.exists('{}/src/drupal'.format(env.workspace)):
             abort('The archive to deploy does not contain a drupal directory.')
 
         if not os.path.isfile('{}/src/drupal/cron.php'.format(env.workspace)):