Split out `CuBIDS.change_filename` into file- and modality-specific functions

[tsalo]

I think it would be nice to have separate functions for identifying and renaming each of the associated files and metadata fields that are flagged in change_filename. Something like:

• rename_dwi, which would call rename_bval, rename_bvec, update_fieldmap_intendedfors, and update_scans_tsv
• rename_func, which would call rename_events, rename_physio, update_fieldmap_intendedfors, and update_scans_tsv
• rename_asl, which would call rename_aslcontext, rename_m0scan, rename_asllabeling, update_fieldmap_intendedfors, and update_scans_tsv