Update ibc transfer adapter contract post-ibc fee decopuling

[NotJeremyLiu]

Background

• The ibc transfer adapter contract was designed to accept a coin param to use as the ibc transfer coin sent the funds field may have had more than 1 coin to satisfy ibc fees
• Since then, the entry point contract logic has changes such that the ibc fee coin is bank sent to the ibc transfer adapter contract separate from the ibc transfer adapter contract call. This means that the ibc transfer adapter contract call will now always only be one coin, and that coin is the same coin to be sent with the ibc transfer

To Explore

• Remove the coin param when calling the ibc transfer adapter contract
• Add a one_coin payment check in the ibc transfer adapter
• Use that coin as the ibc transfer coin