* Use fast_dip3_enforcement instead of fast_dip3_activation
DashTestFramework was refactored before ChainLocks got merged, causing tests
to fail now.
* Move updating of DKG debug status into WaitForNextPhase
Otherwise callers of the RPCs might believe that the next phase has already
started and start producing more blocks, which would then cancel the
current session if it happens faster than the phase handler thread can
progress to the next phase.