[Bugfix] Fix speculative decoding with MLPSpeculator with padded vocabulary

[tjohnson31415]

When using speculative decoding with an MLPSpeculator model that has a vocab_size that is not a multiple of 64 (eg. ibm-granite/granite-7b-instruct), the truncation of the padding in logits_processor was operating on the wrong dimension, so the vocab dimension was not truncated. This would lead to an out-of-bounds type error later in the processing in rejection_sampling.py.

Also, in my debugging I enabled strict_mode to try to catch the error. Even after applying the fix, strict_mode still failed. This is because the order of the arguments was incorrect. I fixed that ordering in this PR as well.

FIX #7212

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[github-actions]

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[njhill]

Thanks @tjohnson31415!