test: get and decode tx with a single gettransaction RPC call
Summary:
Rather than subsequently calling `gettransaction` and `decoderawtransaction` to get the decoded information for a specific tx-id, we can simply use the verbose version of `gettransaction`, which returns this in a 'decoded' key. I.e. node.decoderawtransaction(node.gettransaction(txid)['hex']) can be replaced by: node.gettransaction(txid=txid, verbose=True)['decoded']
Backport of core#23287.
Test Plan:
ninja check-functional
Reviewers: #bitcoin_abc, PiRK
Reviewed By: #bitcoin_abc, PiRK
Differential Revision: https://reviews.bitcoinabc.org/D12597