XGROUP DESTROY should unblock XREADGROUP with -NOGROUP

src/t_stream.c

@@ -1850,6 +1850,8 @@ NULL
             server.dirty++;
             notifyKeyspaceEvent(NOTIFY_STREAM,"xgroup-destroy",
                                 c->argv[2],c->db->id);
+            /* We want to unblock any XREADGROUP consumers with -NOGROUP. */
+            signalKeyAsReady(c->db,c->argv[2]);
         } else {
             addReply(c,shared.czero);
         }