update dependencies

[dominicbarnes]

This PR updates all of the go module dependencies via:

go get -u all
go mod tidy

The main reason I needed this was because the older version of pgconn being depended on here was transitively pulling in a vulnerable version of satori/go.uuid, so updating this here was the easiest way to address that.

It seems like newer versions of go (I'm running 1.18) add these // indirect dependencies to the go.mod, but I believe this is purely informative as the actual dependency tree is not being significantly altered here.