Bug 1508381 - update buglist_creator to use new version of tc client r=tomprince

Differential Revision: https://phabricator.services.mozilla.com/D18117

--HG--
extra : moz-landing-system : lando

python/mozrelease/mozrelease/buglist_creator.py

@@ -10,6 +10,8 @@ import os
 import re
 import requests
 from taskcluster.notify import Notify
+from taskcluster import optionsFromEnvironment
+from taskgraph.util.taskcluster import get_root_url
 from operator import itemgetter
 
 from mozilla_version.gecko import GeckoVersion
@@ -216,11 +218,9 @@ Task group: [{task_group_id}](https://tools.taskcluster.net/groups/{task_group_i
 
     subject = '{} Build of {} {} build {}'.format(subject_prefix, product, version, build_number)
 
-    notify_options = {}
+    notify_options = optionsFromEnvironment({'rootUrl': get_root_url()})
     if 'TASKCLUSTER_PROXY_URL' in os.environ:
-        # Until bug 1460015 is finished, use the old baseUrl style of proxy URL
-        base_url = os.environ['TASKCLUSTER_PROXY_URL'].rstrip('/')
-        notify_options['baseUrl'] = '{}/notify/v1'.format(base_url)
+        notify_options['rootUrl'] = os.environ['TASKCLUSTER_PROXY_URL']
     notify = Notify(notify_options)
     for address in addresses:
         notify.email({