Bug 1431397 - part2: fix release_eta when it's None p=aki r=jlorenzo

--HG--
extra : source : c349de6dc73428fb8b09ff9f416e581dcfe9e05a
extra : amend_source : 2bed7eb11b536b345fb8b30f2d47c85424024ae9

taskcluster/taskgraph/transforms/release_balrog_publishing.py

@@ -15,7 +15,7 @@ transforms = TransformSequence()
 @transforms.add
 def add_release_eta(config, jobs):
     for job in jobs:
-        if config.params['release_eta'] != '':
+        if config.params['release_eta']:
             job['run']['release-eta'] = config.params['release_eta']
 
         yield job