Hotfix: Conditional training cannot use transform.py

[seoulsky-field]

What

If we use conditional_train option "conditional", it doesn't work (first, from transform.py)

Why

While I apply custom_metrics.py to both train.py and conditional_train.py, I found conditional_train.py didn't work well.
Because the conditional_train.py has not updated after @juppak did, some codes could not work.
Also, in the error of transform.py, it can be revised hydra_cfg to hydra_cfg.Dataset.

How

• Also, it has a relation with issue Hotfix: Reorganize conditional_train code #81 , I'll report to @chrstnkgn .
• Revise conditional_train.py to work well

[chrstnkgn]

While I was working on conditional train, I faced the same problem and worked on it. In terms of maintenance, I think there should be quite a change to the conditional trainer code - it may take some time.