Raise RuntimeError for unexpected exceptions when dumping hparams to yaml

[deependujha]

What does this PR do?

Fixes #<issue_number>

Raises a RuntimeError for any unexpected exception during YAML dumping of hyperparameters.
Prevents silent failures and makes it clear which key/value caused the issue.

Aids in debugging issues #19730 and extends PR #19804.

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[deependujha]

not planned.