Add clone impls to some errors

[cameron1024]

Very small PR that adds Clone impls to a couple of error types. I have some error types in my own crate that have Clone bounds, and IMO it's better for the underlying error to implement Clone, rather than chucking it in an Arc.

Thanks 😁

[scarmuega]

Hi @cameron1024 — thanks for the contribution, and apologies for the very long delay in getting back to you.

Since this PR was opened, the repository has been restructured: pallas-miniprotocols and pallas-multiplexer no longer exist (their functionality was folded into pallas-network), so this patch can no longer be rebased as-is. The error types it targeted have been reorganized as well.

If you still need Clone on the current network/error types, we'd be happy to look at a fresh PR against main. Closing this one for housekeeping — thanks again for taking the time.