Remove WalletDatabase::Create, CreateMock, and CreateDummy
Summary:
These are superseded by CreateWalletDatabase, CreateMockWalletDatabase,
and CreateDummyWalletDatabase
This concludes backport of core#19310 [3/3]
https://github.com/bitcoin/bitcoin/pull/19310/commits/da7a83c5ee6a51ff4c3eb35dbd447a310c4a0387
Test Plan: ninja all check-all
Reviewers: #bitcoin_abc, deadalnix
Reviewed By: #bitcoin_abc, deadalnix
Differential Revision: https://reviews.bitcoinabc.org/D9621