Fix session ID for automatic upload

[CodyCBakerPhD]

Automatic upload function automatically adjusts filename to always include session ID, which dandi organize only does when there's more than one session per subject (which we hadn't previously seen in initially shared data)

In this instance, it also depends on the uniqueness of the data_dir_path, which we can't see on the entire MIT side

I can eventually fix the helper in NeuroConv around this condition, but for now this should fix it

Will have to consider if including ses- in nwbfile.session_id is against best practice or not... strictly speaking the DANDI convention is to name file as ..._ses-{session_id}_... so it would be weird to also have ses- in the session ID itself (source of issue here)

[CodyCBakerPhD]

@nwatters01 Also let me know if you want to modify this field in the already existing NWB files instead of reconverting them