update touch webhook

app/jobs/touch_webhook_job.rb

@@ -61,9 +61,10 @@ class TouchWebhookJob < ApplicationJob
 
     when 'PullRequestComment'
       issue_id, sender_id, comment_id = args[0], args[1], args[2]
-      pull = Issue.find_by_id(issue_id).try(:pull_request)
-      comment = pull.issue.comment_journals.find_by_id comment_id
+      issue = Issue.find_by_id(issue_id)
+      comment = issue.comment_journals.find_by_id comment_id
       sender = User.find_by_id sender_id
+      pull = issue.try(:pull_request)
       return if pull.nil? || sender.nil? || comment.nil?
 
       pull.project.webhooks.each do |webhook|