use experiment name in torchx runner TB path

Summary: for compatbility with benchmarking suite. otherwise, TB logs of the same trial_idx are stored in the same directory across replications

Reviewed By: lena-kashtelyan

Differential Revision: D35516090

fbshipit-source-id: 6c21f21670633a24deeed414ae885c5dc5cd4263

ax/runners/torchx.py

@@ -145,6 +145,9 @@ def run(self, trial: BaseTrial) -> Dict[str, Any]:
             if "trial_idx" in component_args:
                 parameters["trial_idx"] = trial.index
 
+            if "experiment_name" in component_args:
+                parameters["experiment_name"] = trial.experiment.name
+
             if "tracker_base" in component_args:
                 parameters["tracker_base"] = self._tracker_base