update the test after merge

after d7d3ad69 debug_sync waits are no longer interrupted by
soft kills that server shutdown is using. Luckily in this test
there's no need to wait, it wants the commit to be properly completed,
fully committed in both engines.

mysql-test/suite/binlog/r/binlog_truncate_multi_engine.result

@@ -145,7 +145,7 @@ INSERT INTO t2 VALUES (1, REPEAT("x", 1));
 BEGIN;
 INSERT INTO t2 VALUES (2, REPEAT("x", 4100));
 INSERT INTO t1 VALUES (2, REPEAT("x", 4100));
-SET DEBUG_SYNC= "commit_after_run_commit_ordered SIGNAL con1_ready WAIT_FOR signal_no_signal";
+SET DEBUG_SYNC= "commit_after_run_commit_ordered SIGNAL con1_ready";
 COMMIT;
 connection default;
 SET DEBUG_SYNC= "now WAIT_FOR con1_ready";

mysql-test/suite/binlog/t/binlog_truncate_multi_engine.test

@@ -47,7 +47,7 @@ CREATE TABLE t2 (a INT PRIMARY KEY, b MEDIUMTEXT) ENGINE=rocksdb;
 
 --let $case = "C"
 --let $description= "both engines have committed its transaction branch"
---let $debug_sync_action = "commit_after_run_commit_ordered SIGNAL con1_ready WAIT_FOR signal_no_signal"
+--let $debug_sync_action = "commit_after_run_commit_ordered SIGNAL con1_ready"
 # Hold off after both engines have committed. The server is shut down.
 --let $shutdown_timeout=
 --let $restart_parameters = --rpl-semi-sync-slave-enabled=1 --sync-binlog=1