Issue Addressed

Fix new warnings from new Rust beta compiler (rustc 1.75.0-beta.1).

Also:

• Add clippy::enum_variant_names to allowed list. We prefer Error::BeaconStateError over Error::BeaconState.
• Ignore some unused_imports in watch::database as they seem to be false positives. We could probably change the way we do imports within watch as it isn't used elsewhere, but it won't allow us to arrange it the way it currently is, i.e. re-exporting database related functions via the watch::database module.