[Thinkit] Host is expected to reboot during the test. Hence disabled check for validating link flaps during the test.Add host linkup tests to test tracker Make random_blackbox_events_test read P4 Info from switch if none is passed in.Update linerate traffic test to replace IxiaHelper with OTG client.

[Thinkit] Host is expected to reboot during the test. Hence disabled check for validating link flaps during the test.Add host linkup tests to test tracker Make random_blackbox_events_test read P4 Info from switch if none is passed in.Update linerate traffic test to replace IxiaHelper with OTG client. #4343