[backport#15632] [wallet] Remove unnecessary Chain::Lock parameter from ResendWalletTransactions

Summary:
https://github.com/bitcoin/bitcoin/pull/15632/commits/833d98ae073daf0f25f786f043f2ffa85155c8ff

This completes the backport of Core PR15632

Test Plan:

cmake .. -GNinja -DENABLE_WERROR=ON
ninja check-all

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D6032