Move getRegistry to registry package

[nambrot]

Move https://github.com/hyperlane-xyz/hyperlane-monorepo/blob/nambrot/infra-checker-use-registry/node_modules/@hyperlane-xyz/cli/src/context/context.ts#L191 into the registry package, as it is not CLI specific

[mshojaei-txfusion]

I created these two PRs, one with OOP and the other one with functions,
@nambrot please take a look and let me know which one makes more sense so I would use it for mono-repo PR.

[I did this because registry code is implemented with classes and OOP, And IMO as we are moving more stuff from mono-repo to registry, that could be good idea to make a registry factory class for this case]