getTxMetadata -> getTxAuxiliaryData

[klntsky]

We only get the Metadata part of AuxiliaryData in our query layer. We should get everything.

It was partially done for the Ogmios/kupo backend here:

https://github.com/Plutonomicon/cardano-transaction-lib/pull/1624/files#diff-5bba4350fa4ec12283cf36c3245ee1d593b33ad3cef8310f79c0ec4314c6bd69

But we need it for the Blockfrost backend as well. It should be done by querying for the whole transaction contents and getting just the auxiliary data.

The PR should be based on #1624