Upgrade the dcrwallet dependency to pick up the new version of txrules.StakePoolTicketFee which considers the status of DCP0012 in its fee calculation.
This change was made in the past (#435) but needed to be reverted (#454) because clients were not updated to use the new calculation. This change can now go back in as of the dcrwallet/decrediton 2.0 release.
Upgrade the dcrwallet dependency to pick up the new version of txrules.StakePoolTicketFee which considers the status of DCP0012 in its fee calculation.