narval #3916982 stopping narval takes forever [validation pending]

when getting SIGTERM, the process manager should kill its jobs and exit immediately. atm it takes a while.

prioritynormal
typebug
done in4.1.0
load0.250
load left0.000
closed by#6d9e2c3b823c [bot] kill tasks on exit (closes #3916982)
patch[bot] kill tasks on exit (closes #3916982) [applied]