Log metrics along with hparams in TensorBoardCallback
# 🚀 Feature request

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Log metrics along with hparams in TensorBoardCallback.

## Motivation

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It seems useless to log hparams with empty metric dict because the training arguments are already logged in the text section. Now users can see only a blank screen when they click on the HPARAMS of the TensorBoard. So I think it will be better to call `add_hparams` with evaluation metrics when available. Otherwise just don't call this function.


This issue has been automatically marked as stale and been closed because it has not had recent activity. Thank you for your contributions.

If you think this still needs to be addressed please comment on this thread.