Bug 1519472: Disable caches on windows repackage builds; r=aki a=tomprince

They appear to be causing tasks to take several hours to complete.

Differential Revision: https://phabricator.services.mozilla.com/D21775

--HG--
extra : rebase_source : a55cfc24527662427bbeccf0d03f97dca047a3cb
extra : amend_source : 5e352a1ff382353460fdd143d7d0ba52251a5b8a

taskcluster/taskgraph/transforms/repackage.py

@@ -312,6 +312,7 @@ def make_job_description(config, jobs):
         if build_platform.startswith('win'):
             worker_type = 'aws-provisioner-v1/gecko-%s-b-win2012' % level
             run['use-magic-mh-args'] = False
+            run['use-caches'] = False
         else:
             if build_platform.startswith(('linux', 'macosx')):
                 worker_type = 'aws-provisioner-v1/gecko-%s-b-linux' % level