osmo-gsm-tester: add test case: Test 2nd trx is correctly used
We may need to add a "supported_trx" config in resources.conf to specify how many TRX can a given BTS support. This way we can use scenarios to filter for a BTS which supports that number of TRX (but we cannot match for <=, need to think more about it). Alternatively, we can use one of the BTS that we now supports it, like ":octphy".
To test that the 2nd trx is used correctly, we can use an already existing BSC/BTS VTY cmd called "channel allocator" which can have parameters "ascend" or "descend".
One of those options changes the algo used to allocate channels to start from the latest one available, ie. last timeslot in the 2nd TRX.
We can use that and place a voice call and make sure somehow that the 2nd TRX is being used (checking the log file?).