Why do we give out validator signing keys via the RPC?

[hrxi]

I think it's not considered good practice to provide cryptographic material via some RPC method, but we currently do it:

core-rs-albatross/rpc-server/src/dispatchers/validator.rs

Lines 37 to 63 in 53f251d

	async fn get_signing_key(&mut self) -> RPCResult<String, (), Self::Error> {
	Ok(hex::encode(self.validator.signing_key.read().private.serialize_to_vec()).into())
	}
	async fn get_voting_key(&mut self) -> RPCResult<String, (), Self::Error> {
	Ok(hex::encode(
	self.validator
	.voting_keys
	.read()
	.get_current_key()
	.secret_key
	.serialize_to_vec(),
	)
	.into())
	}
	async fn get_voting_keys(&mut self) -> RPCResult<Vec<String>, (), Self::Error> {
	Ok(self
	.validator
	.voting_keys
	.read()
	.get_keys()
	.into_iter()
	.map(|key| hex::encode(key.secret_key.serialize_to_vec()))
	.collect::<Vec<String>>()
	.into())
	}