MDEV-25958: rpl_semi_sync_fail_over.test fails in buildbot

Post push fix.

Added a missing WAIT_FOR signal line.

mysql-test/suite/rpl/r/rpl_semi_sync_fail_over.result

@@ -180,6 +180,7 @@ connect  conn_client,127.0.0.1,root,,test,$SERVER_MYPORT_1,;
 SET DEBUG_SYNC= "commit_before_get_LOCK_commit_ordered SIGNAL con1_ready WAIT_FOR con1_go";
 INSERT INTO t1 VALUES (7, REPEAT("x", 4100));
 connect  conn_client_3,127.0.0.1,root,,test,$SERVER_MYPORT_1,;
+SET DEBUG_SYNC= "now WAIT_FOR con1_ready";
 SET DEBUG_SYNC= "commit_before_update_binlog_end_pos SIGNAL con3_ready WAIT_FOR con1_go";
 INSERT INTO t1 VALUES (8, REPEAT("x", 4100));
 connection server_1;

mysql-test/suite/rpl/t/rpl_semi_sync_crash.inc

@@ -51,6 +51,7 @@ if ($case == 3)
   SET DEBUG_SYNC= "commit_before_get_LOCK_commit_ordered SIGNAL con1_ready WAIT_FOR con1_go";
   --send_eval $query_to_crash
   --connect (conn_client_3,127.0.0.1,root,,test,$SERVER_MYPORT_1,)
+  SET DEBUG_SYNC= "now WAIT_FOR con1_ready";
   # use the same signal with $query_to_crash
   SET DEBUG_SYNC= "commit_before_update_binlog_end_pos SIGNAL con3_ready WAIT_FOR con1_go";
   --send_eval $query2_to_crash