Respond with unauth

[Sjors]

I'm turning some TODO's into Github issues.

This one seems potentially useful for debugging:

cln-nostr-wallet-connect/src/main.rs

Lines 247 to 252 in 6450ad9

	// Check event is from correct pubkey
	if event.pubkey.ne(&connect_client_keys.public_key()) {
	// TODO: Should respond with unauth
	info!("Event from incorrect pubkey: {}", event.pubkey.to_string());
	continue;
	}