Fix needed for Chapter 5 [Fact]

[editor-Ajian]

Describe the error
In the section "Channel Management - Getting Inbound Liquidity", the 858 line:

* Use a submarine swap (e.g., Loop In) to exchange on-chain BTC for an inbound channel to your node.

When using Loop In, you pay on-chain BTC to get lightning balance, i.e. outbound capacity. If you want inbound capacity, you should run Loop Out, pay your lightning balance to get on-chain BTC, at the same time getting inbound capacity.

To Fix

Change it to:

* Use a submarine swap (e.g., Loop Out) to pay out your lightning balance, getting on-chain BTC while getting inbound liqudity.