docs/releasing: add a note that commits should simmer in master before being cherry-picked
/cc @dbaker
I've added local modifications to the pick-ui
script to show when a commit is too young, while still allowing the maintainer to choose to ignore that and cherry-pick it anyway in case it's really urgent.
I'll MR that along with the rest of my pick-ui
changes once !3608 (merged) is merged.