Add Database helper type: Either

[mattsse]

Describe the feature

under some circumstances it might be useful to use two different Database implementations.
we currently don't have an Either type for this

eventually this should be upstreamed to revm directly, but we can introduce this here first

reth/crates/revm/src/lib.rs

Line 15 in 460e26c

pub mod database;

TODO

• add new modules mod either and enum Either that implements Database if both variants implement database.

pub enum Either<L, R> {
    /// A value of type `L`.
    Left(L),
    /// A value of type `R`.
    Right(R),
}

Additional context

No response

[Parikalp-Bhardwaj]

Hi @mattsse 🙌