run rpc_signrawtransaction with --descriptors

Summary:
This test works without any changes, for Bitcoin ABC.
For Bitcoin Core, there were some changes in segwit related tests.

This is a backport of [[bitcoin/bitcoin#18788 | core#18788]] [6/15]

bitcoin/bitcoin@0bd1860

Test Plan: `test/functional/test_runner.py rpc_signrawtransaction`

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D10659

test/functional/test_runner.py

@@ -106,6 +106,7 @@
     "rpc_createmultisig.py": [["--descriptors"]],
     "rpc_deriveaddresses.py": [["--usecli"]],
     "rpc_fundrawtransaction.py": [["--descriptors"]],
+    "rpc_signrawtransaction.py": [["--descriptors"]],
     # FIXME: "rpc_psbt.py": [["--descriptors"]],
     "wallet_avoidreuse.py": [["--descriptors"]],
     "wallet_balance.py": [["--descriptors"]],