This merge request aims to make the random seeding used in LAr and Tile Digitization as similar as possible to the seeding used in 21.0, while still being thread-safe.
In particular it fixes a bug introduced in !25992 (merged), where the random number stream was
re-seeded every time
LArTTL1Maker::computeNoise(...) was called rather than once per
NB in 21.0
all shared a common random stream. If they were run in the same job in 21.0
this would cause interference between them (I don't think they were).
Even after the changes in this merge request, the random streams will still be
distinct in master.