Make use of generic in go bindings

The current go bindings are not using [generics](https://go.dev/blog/intro-generics) but those might be a good fit for the bindings to not require a user to return an `interface{}` and parse it again. Using an `interface{}` always requires that a user does a type conversion after the `Transact` call e.g. https://github.com/FoundationDB/fdb-kubernetes-operator/blob/main/fdbclient/lock_client.go#L63-L71. I haven't looked to deep into the go bindings right know to see if we could make use of generics but I think that would be a good approach.

I created this issue to discuss this as using go generics would require go 1.18 from our clients.

Start by locating the Go bindings and the Transact call, then compare their current interface{} return behavior with the usage example in fdbclient/lock_client.go. The issue does not identify specific binding files or tests; first establish whether generics fit the API and determine the required Go 1.18 compatibility changes before defining completion criteria.

Written by the indexing model from the issue text.