Fix flakiness for rpl.rpl_innodb_auto_increment

Summary:
These tests fail occasionally due to an error message about the
    channel being stopped in the error log. Suppress this error message.

Squash: D45573014

Differential Revision: D44844728

fbshipit-source-id: a9238e4

Author: Luqun Lou

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

@@ -4,6 +4,7 @@ Note	####	Sending passwords in plain text without SSL/TLS is extremely insecure.
 Note	####	Storing MySQL user name or password information in the master info repository is not secure and is therefore not recommended. Please consider using the USER and PASSWORD connection options for START SLAVE; see the 'START SLAVE Syntax' in the MySQL Manual for more information.
 [connection master]
 CALL mtr.add_suppression("Unsafe statement written to the binary log using statement format since BINLOG_FORMAT = STATEMENT.");
+call mtr.add_suppression("The slave coordinator and worker threads are stopped");
 [connection slave]
 CHANGE REPLICATION SOURCE TO SOURCE_CONNECT_RETRY = 30 ;
 include/start_slave.inc

mysql-test/suite/rpl/t/rpl_innodb_auto_increment.test

@@ -22,6 +22,7 @@
 --source include/big_test.inc
 
 CALL mtr.add_suppression("Unsafe statement written to the binary log using statement format since BINLOG_FORMAT = STATEMENT.");
+call mtr.add_suppression("The slave coordinator and worker threads are stopped");
 
 # Increasing master_connect_retry to increase the time interval between connection retries due to Bug#23615424:
 # WL#6338: RPL.RPL_INNODB_AUTO_INCREMENT FAILS WITH ERROR IN SYNC_WITH_MASTER.INC