BUG#49562: SBR out of sync when using numeric data types + user

variable

Incremental commit: 
  1. Moved part of the test case to binlog suite.
  2. Removed cast set when writing the flags field.

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

@@ -135,11 +135,6 @@ TRUNCATE t1;
 -- echo ## check: contents of both tables master's and slave's
 -- enable_warnings
 
--- echo ## assertion: checks that User_var_log_event::pack_info correctly
--- echo ## displays the binlog content by taking into account the
--- echo ## unsigned_flag
--- source include/show_binlog_events.inc
-
 ## cleanup
 -- connection master
 DROP TABLE t1;