[Bugfix] Fix tests/kernels/test_mamba_ssm_ssd.py

[tlrmchlsmth]

Fixes tests which are busted on main:

kernels/test_mamba_ssm_ssd.py::test_mamba_chunk_scan_cont_batch[seq_len_chunk_size_cases1-32-4-itype0] - AssertionError: chunk_indices and chunk_offsets should have been set

(These were broken by #15423, which made these arguments, and mandatory in this case)

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