plugin misc_groupblog: pubsub response do not fail when target server doesn't handle RSM

src/plugins/plugin_misc_groupblog.py

@@ -508,7 +508,10 @@ class GroupBlog(object):
                 - couple (comments data, RSM response data for the comments)
         """
         def comments_cb(comments_data, entry):
-            entry['comments_count'] = comments_data[1]['count']
+            try:
+                entry['comments_count'] = comments_data[1]['count']
+            except KeyError:  # target pubsub server probably doesn't handle RSM
+                pass
             return (entry, comments_data) if max_ > 0 else entry
 
         assert max_ >= 0