fix: sort tokens in join pool to avoid panic

[matthiasmatt]

Description

Join pool for unsorted token generate a panic and it should not be up to the user to sort them in the transaction.

found in py-sdk with:

nibiru.msg.MsgJoinPool(
                sender=agent.address,
                pool_id=pool_ids["uusdc:unusd"],
                tokens=[Coin(100, "uusdc"), Coin(100, "unusd")],
            ),

Purpose

QoL