utxoupdatepsbt does not fill in input assetids.

[roconnor-blockstream]

In the master branch as of 1ba24fe9b3cc3ad1166ed93a0969602d0c7898ff running updateutxopsbt only fills in the amounts of the input into the witness_info. For taproot we will also need the assetID filled in.

P.S. we may want to rename the commands to say pset instead of psbt.