Add send and check reply packet function for multi-devices tests

The `send_packet_and_expect_reply_received` start capurting packets,
and then send out request packets, then get expected packets counts to validate.
In the end, stop capturing for the specified interface.

Test: m connectivity_multi_devices_snippet && atest CtsConnectivityMultiDevicesTestCases
Change-Id: I275534a45ce0ed363fa8ab9d12272d25845aa598
1 file changed