ethexe: slash peer/validator in case of network request errors

[grishasobol]

Problem to Solve

Presently processing of network request error is not considering as service execution work finish with error

gear/ethexe/cli/src/service.rs

Lines 502 to 512 in cdb5aa7

	let result = Self::process_network_message(
	message,
	&db,
	validator.as_mut(),
	sequencer.as_mut(),
	network_sender.as_mut(),
	);
	if let Err(err) = result {
	log::warn!("Failed to process network message: {:?}", err);
	}

Consider to slash peer/validator which send such requests.

Possible Solution

Notes

No response

[grishasobol]

Also consider whether we should use log::error instead of log::warn in network request processing error case