Mismatch in files being created for Neuropixels 2.0 headstage

[bparks13]

In the Neuropixels 2.0e workflow, the AmplifierData is being written to np2-a-ephys_.raw and np2-b-amp_.raw. Presumably we want these to be coherent with the loading data script, which has np2-b-ephys_{suffix}.raw as the expected filename.