[tests] Rename rpc_listtransactions.py to wallet_listtransactions.py

Summary:
listtransactions is a wallet RPC. The test name should indicate that
this is a wallet test.

Partial backport of Core PR12953
https://github.com/bitcoin/bitcoin/pull/12953/commits/4e671f0353beaa3759f2069569f05239c0be89cf

Depends on D3949

Test Plan:

test_runner.py

Reviewers: deadalnix, Fabien, jasonbcox, O1 Bitcoin ABC, #bitcoin_abc

Reviewed By: Fabien, O1 Bitcoin ABC, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D4361