increased shm no longer required for arti reproducible builds

changes made in #110 (closed) are no longer required for Arti (tpo/core/arti!818 (merged)). Maybe they can be reverted, maybe they are required for other things. Notably Shadow also use shm, but only a few runners are concerned by Shadow whereas every TPA runner had its shm made bigger for Arti.

All runners have been setup to be compatible with shadow jobs, hence we still require a rather large /dev/shm on all of them. For details see here: team#40833 (comment 2835576)

added Doing label

added CI label

closed