[HOTFIX] Bug in merge script

dev/merge_spark_pr.py

@@ -266,10 +266,9 @@ def resolve_jira_issue(merge_branches, comment, default_jira_id=""):
 
     resolve = filter(lambda a: a['name'] == "Resolve Issue", asf_jira.transitions(jira_id))[0]
     resolution = filter(lambda r: r.raw['name'] == "Fixed", asf_jira.resolutions())[0]
-    custom_fields = {'resolution': {'id': resolution.raw['id']}}
     asf_jira.transition_issue(
         jira_id, resolve["id"], fixVersions = jira_fix_versions, 
-        comment = comment, fields = custom_fields)
+        comment = comment, resolution = {'id': resolution.raw['id']})
 
     print "Successfully resolved %s with fixVersions=%s!" % (jira_id, fix_versions)