Remove thank you message

As this was posted as it's own comment, it was found to be a bit spammy.

The long term fix for this is to have a *single* message when Issues/PRs
are created, see
ansible#1081 (comment)

ansibullbot/triagers/ansible.py

@@ -806,18 +806,6 @@ def create_actions(self, iw, actions):
                 if u'needs_triage' not in actions.unlabel:
                     actions.unlabel.append(u'needs_triage')
 
-        # Thank submitter
-        if iw.created_at > datetime.datetime(2018, 10, 11): # before, PR could already have been thanked
-            previous_comment = iw.history.last_date_for_boilerplate(u'thank_submitter')
-            if not previous_comment:
-                tvars = {
-                    u'submitter': iw.submitter,
-                    u'is_pullrequest': iw.is_pullrequest(),
-                }
-                comment = self.render_boilerplate(tvars, boilerplate=u'thank_submitter')
-                if comment not in actions.comments:
-                    actions.comments.insert(0, comment) # thank should be first comment
-
         # owner PRs
         if iw.is_pullrequest():
             if self.meta[u'owner_pr']:

templates/issue_missing_data.j2

@@ -1,4 +1,4 @@
-@{{ submitter }}: in order for the community to handle your {{ itype }} effectively, we need a bit more information.
+@{{ submitter }}: Greetings! Thanks for taking the time to open this {{ itype }}. In order for the community to handle your {{ itype }} effectively, we need a bit more information.
 
 Here are the items we could not find in your description:
 {% for item in missing_sections %}