Bug#18949527 SUITE/BINLOG/T/BINLOG_KILLED.TEST FORGETS TO

             DISCONNECT CON1 AND CON2
  
Problem:
The test suite/binlog/t/binlog_killed.test makes the connections
con1 and con2 but forgets to disconnect them + wait till that
operation is finished at test end.
This mistake has the potential to harm subsequent tests in
case these tests depend on the content of the processlist.
 
Solution:
Added disconnect + wait_until_disconnected.inc 
within the test cleanup.

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

@@ -340,6 +340,14 @@ drop function bug27563;
 # common cleanup 
 #
 
+connection con1;
+disconnect con1;
+--source include/wait_until_disconnected.inc
+connection con2;
+disconnect con2;
+--source include/wait_until_disconnected.inc
+connection default;
+
 drop table t1,t2,t3;
 
 --echo end of the tests