Fix for issue jenkinsci#29

Author: aaronjwhiteside

src/main/java/org/jenkinsci/plugins/pipeline/github/trigger/GitHubEventSubscriber.java

@@ -75,8 +75,6 @@ protected void onEvent(final GHSubscriberEvent event) {
     }
 
     private void handleIssueComment(final GHSubscriberEvent event) {
-        GHEventPayload.IssueComment issueCommentEvent;
-
         // we only care about created or updated events
         switch (event.getType()) {
             case CREATED:
@@ -87,6 +85,7 @@ private void handleIssueComment(final GHSubscriberEvent event) {
         }
 
         // decode payload
+        final GHEventPayload.IssueComment issueCommentEvent;
         try {
             issueCommentEvent = GitHub.offline()
                     .parseEventPayload(new StringReader(event.getPayload()), GHEventPayload.IssueComment.class);
@@ -95,6 +94,16 @@ private void handleIssueComment(final GHSubscriberEvent event) {
             return;
         }
 
+        switch (issueCommentEvent.getAction()) {
+            case "created":
+            case "edited":
+                break;
+            default:
+                LOG.debug("Ignoring IssueComment: {} with Action: {}",
+                        issueCommentEvent.getComment(), issueCommentEvent.getAction());
+                return;
+        }
+
         // create key for this comment's PR
         final String key = String.format("%s/%s/%d",
                 issueCommentEvent.getRepository().getOwnerName(),