Improve error messaging for ASR pipeline.
- Raise error early (in `_sanitize`) so users don't waste time trying to
run queries with invalid params.
- Fix the error was after using `config.inputs_to_logits_ratio` so our
check was masked by the failing property does not exist.
- Added some manual check on s2t for the error message.
No non ctc model seems to be used by the default runner (they are all
skipped).
