R1:5e7b316fbed1

Free task leases on "phd start"

Summary:
Fixes T5154. Currently, "phd stop" terminates daemons relatively abruptly (and other things do too, like killing them). This can leave them with long leases that won't expire any time soon. Normally this isn't a big deal, since it just means an email or an import takes a bit longer (often 2 hours, but up to 24 hours) to run. However:

- We've increased default lease durations a lot fairly recently -- the 2 hours used to be 15 minutes.
- Harbormaster and Drydock…