MDEV-28970: Add RESET MASTER to clear possible remaining binlog from previous test

mysql-test/suite/plugins/r/test_sql_service.result

+reset master;
 install plugin test_sql_service soname 'test_sql_service';
 show status like 'test_sql_service_passed';
 Variable_name	Value

mysql-test/suite/plugins/t/test_sql_service.test

 --source include/not_embedded.inc
 --source include/have_log_bin.inc
 
+reset master; # clear binlogs
+
 if (!$TEST_SQL_SERVICE_SO) {
   skip No TEST_SQL_SERVICE plugin;
 }