Bump persistent-postgresql version to match hackage (2.1.2.2).
Bump persistent-postgresql version to match hackage (2.1.2.2).

gbwey/persistent,mitchellwrosen/persistent,nakaji-dayo/persistent,greydot/persistent,erikd/persistent,jasonzoladz/persistent,creichert/persistent,jasonzoladz/persistent,andrewthad/persistent,jasonzoladz/persistent,superduper/persistent,naushadh/persistent,yesodweb/persistent,nakaji-dayo/persistent,meteficha/persistent,meteficha/persistent,andrewthad/persistent,mitchellwrosen/persistent,gbwey/persistent,rdnetto/persistent,pseudonom/persistent,mkscrg/persistent,psibi/persistent,bitemyapp/persistent,jcristovao/persistent,greydot/persistent,superduper/persistent,mkscrg/persistent,plow-technologies/persistent,mitchellwrosen/persistent,rdnetto/persistent,greydot/persistent,jcristovao/persistent,paul-rouse/persistent,jcristovao/persistent,meteficha/persistent,superduper/persistent,nakaji-dayo/persistent,pseudonom/persistent,mkscrg/persistent,gbwey/persistent,andrewthad/persistent