On unfollow, also delete from the pending follow list.

activitypub.c

@@ -1972,6 +1972,11 @@ int process_input_message(snac *snac, const xs_dict *msg, const xs_dict *req)
                     snac_log(snac, xs_fmt("no longer following us %s", actor));
                     do_notify = 1;
                 }
+                else
+                if (pending_check(snac, actor)) {
+                    pending_del(snac, actor);
+                    snac_log(snac, xs_fmt("cancelled pending follow from %s", actor));
+                }
                 else
                     snac_log(snac, xs_fmt("error deleting follower %s", actor));
             }