Revert "Safely import optional python packages (#13936)"

[chtruong814]

This reverts commit e04ee42.

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Revert "Safely import optional python packages (#13936)"

This was able to merge without the CI running. And it seems some failures are happening on subsequent tests:
https://github.com/NVIDIA/NeMo/actions/runs/16218093086/job/45792718838

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[chtruong814]

Verified that this fixes the failing test after manually running this on a CI machine. Moving forward with the revert to unblock other PRs. I think I know the issue and will open a new PR with a fix.