SONiC-utilities submodule update:

* 553936b (HEAD, origin/master, origin/HEAD, master) route_check: Fix hanging & logging level (sonic-net#1520)
* ed45412 [show][config] add support for setting and displaying switching modes on Y cable (sonic-net#1501)
* bf46638 Handling error scenario of adding port to Vlan which is part of LAG (sonic-net#1516)
* ae39883 Fix bug: show vlan config for vlan with no members (sonic-net#1503)
* 3a482ac [test] Update unit test coverage for command 'show mac' (sonic-net#1504)
* 4a0c010 [config] Disable/enable container monitoring when stopping/starting services (sonic-net#1499)