[cairo/ibc-core] only relayer should submit commitment proofs

[rnbguy]

After #204, we now validate the sender in the client contract.

ibc-starknet/cairo-contracts/packages/clients/src/cometbft/component.cairo

Lines 61 to 67 in 4c63248

	fn update_client(
	ref self: ComponentState<TContractState>, msg: MsgUpdateClient
	) -> UpdateResponse {
	self.assert_owner();
	self.update_validate(msg.clone());
	self.update_execute(msg)
	}

But we also need to authenticate the ibc-core messages that require membership proofs. Otherwise, spammers can submit empty dummy proofs successfully against any updated state root.

For example, for chan_open_try should start with a similar self.assert_owner() call here.

ibc-starknet/cairo-contracts/packages/core/src/channel/components/handler.cairo

Lines 78 to 84 in 4c63248

	fn chan_open_try(
	ref self: ComponentState<TContractState>, msg: MsgChanOpenTry
	) -> ChannelId {
	let channel_sequence = self.read_next_channel_sequence();
	self.chan_open_try_validate(channel_sequence, msg.clone());
	self.chan_open_try_execute(channel_sequence, msg)
	}

We should do it for other handlers like conn_open_try, chan_open_ack, recv_packet, ack_packet etc -- anything that requires commitment proofs.