text: Title: HPO: gpu_metrics file does not exist!
  Body: **Describe the issue**:
  I run`nnictl create --config exp.yaml --port 9090` and  cheak `nvidia-smi`, find its running without using GPU.
  So  I run`nnictl create --config exp.yaml --port 9090 - f` and get error below:
  ![image](https://user-images.githubusercontent.com/19604387/164359111-4e2dd2ac-33ae-466f-b21d-774ff51977af.png)
  
  I have followed tips in https://github.com/microsoft/nni/issues/4226
  `METRIC_OUTPUT_DIR=${scriptFolder} python3 -m nni.tools.gpu_tool.gpu_metrics_collector` works under my path.
  
  **Environment**:
  - NNI version: 2.6
  - Training service (local|remote|pai|aml|etc): local
  - Client OS: Ubuntu 18.04
  - Server OS (for remote mode only): \
  - Python version:  py3.7
  - PyTorch/TensorFlow version:  pytorch 1.10.2
  - Is conda/virtualenv/venv used?: Y
  - Is running in Docker?: N
  
  
  **Configuration**:
   - Experiment config (remember to remove secrets!):
   - Search space:
  ![image](https://user-images.githubusercontent.com/19604387/164230399-10b95038-ce0d-4e3b-b6d5-1f118a78e76f.png)
  
  **Log message**:
   - nnimanager.log:
   Dont exist
   - dispatcher.log:
  [2022-04-20 20:12:10] INFO (nni.experiment/MainThread) Creating experiment, Experiment ID: 30pecn7s
  [2022-04-20 20:12:10] INFO (nni.experiment/MainThread) Starting web server...
  [2022-04-20 20:12:11] WARNING (nni.experiment/MainThread) Timeout, retry...
  [2022-04-20 20:12:12] INFO (nni.experiment/MainThread) Setting up...
  [2022-04-20 20:12:12] INFO (nni.experiment/MainThread) Web UI URLs: http://127.0.0.1:9090 http://172.17.7.99:9090 http://172.18.0.1:9090 http://172.19.0.1:9090 http://172.20.0.1:9090
  [2022-04-20 20:12:12] INFO (nni.tools.nnictl.launcher/MainThread) To stop experiment run "nnictl stop 30pecn7s" or "nnictl stop --all"
  [2022-04-20 20:12:12] INFO (nni.tools.nnictl.launcher/MainThread) Reference: https://nni.readthedocs.io/en/stable/Tutorial/Nnictl.html
  [2022-04-20 20:12:12] INFO (nni.experiment/MainThread) Stopping experiment, please wait...
  [2022-04-20 20:12:12] INFO (nni.tuner.tpe/MainThread) Using random seed 1504156515
  [2022-04-20 20:12:12] INFO (nni.runtime.msg_dispatcher_base/MainThread) Dispatcher started
  [2022-04-20 20:12:12] INFO (nni.runtime.msg_dispatcher_base/MainThread) Dispatcher exiting...
  [2022-04-20 20:12:15] INFO (nni.runtime.msg_dispatcher_base/MainThread) Dispatcher terminiated
   - nnictl stdout and stderr:
   Dont exist
  
  **How to reproduce it?**:
  nnictl create --config exp.yaml --port 9090 - f
  