TrigValSteering: Add AthFile outputs to log merging step
Adding AthFile logs to the log merging procedure, as they often hide the real reason for job failure like it happened in ATR-21094. For now this is only done for tests using Reco_tf for two reasons:
- It was trivial to add for this case and not so easy for others
- Such issues typically happen in TrigAnalysisTest tests with Reco_tf because they test integration between different production steps