transaction: for witness v0 txins, put both UTXO and WIT_UTXO in psbt

Until now we have been only putting PSBT_IN_NON_WITNESS_UTXO (="UTXO", full tx)
in segwit witness v0 txins, as signers wanted the full tx anyway due to
bip-143 sighash issue [0], and as WITNESS_UTXO can be calculated from UTXO.

My reading of bip-174 is that either behaviour is correct, but
achow101 said bip-174 expects PSBT_IN_WITNESS_UTXO for segwit inputs.
Regardless, including both fields does not increase the tx size too much
(UTXO can be very large ofc but we were already including that, WIT_UTXO is small).
This also might increase compatibility with some other software - I've found
some issues where this might have been the culprit [1][2][3].

closes https://github.com/spesmilo/electrum/issues/8039

related:
[0] https://github.com/spesmilo/electrum/pull/6198
[1] https://github.com/cryptoadvance/specter-desktop/issues/868
[2] https://github.com/cryptoadvance/specter-desktop/issues/1046
[3] https://github.com/cryptoadvance/specter-desktop/issues/1544

electrum/tests/__init__.py

@@ -36,6 +36,8 @@ class SequentialTestCase(unittest.TestCase):
 class ElectrumTestCase(SequentialTestCase):
     """Base class for our unit tests."""
 
+    # maxDiff = None
+
     def setUp(self):
         super().setUp()
         self.asyncio_loop, self._stop_loop, self._loop_thread = util.create_and_start_event_loop()