Remove manual prompt based signing path from forc-client

[kayagokalp]

From couple of years ago, at the time we first introduced forc-deploy, we did not have any way of signing transactions other than manual copy pasting in between multiple terminals. This was resolved with forc-wallet integration but the old path is still in the code. We should remove it as it is pretty outdated, although working probably confusing for someone new into the codebase and makes some new stuff little bit harder than it needs to be like #6069

Basically remove:

sway/forc-plugins/forc-client/src/util/tx.rs

Lines 41 to 56 in f342f52

	fn prompt_address() -> Result<Bech32Address> {
	print!("Please provide the address of the wallet you are going to sign this transaction with:");
	std::io::stdout().flush()?;
	let mut buf = String::new();
	std::io::stdin().read_line(&mut buf)?;
	Bech32Address::from_str(buf.trim()).map_err(Error::msg)
	}
	fn prompt_signature(tx_id: fuel_tx::Bytes32) -> Result<Signature> {
	println!("Transaction id to sign: {tx_id}");
	print!("Please provide the signature:");
	std::io::stdout().flush()?;
	let mut buf = String::new();
	std::io::stdin().read_line(&mut buf)?;
	Signature::from_str(buf.trim()).map_err(Error::msg)
	}

and places calling into these functions.