Path length too long in fmriprep

[baxpr]

fmriprep crashes at the midthickness0 node if path of working dir has too many characters.

Refs:
https://bug.xnat.vanderbilt.edu/bugzilla/show_bug.cgi?id=2986#c99
https://bug.xnat.vanderbilt.edu/bugzilla/show_bug.cgi?id=2943#c57
https://neurostars.org/t/midthickness0-node-crash-during-fmriprep-23-1-4/26592/14

dax is putting everything in a temp dir like /tmp/NDW_HOTC-x-10500051020-x-10500051020-x-test-071405-fmriprep-HOTC2mm_v23-x-484572aa.WDnBDkvIP

Can we get a much shorter temp dir name without causing logging/bookkeeping problems? The mktemp autonaming part WDnBDkvIP should be avoiding collisions for us already.