cli: create GetNewAddress()
Summary:
This is a backport of core#19133 [3/10]
https://github.com/bitcoin/bitcoin/pull/19133/commits/f7c65a33508c4bb8e9ed896e150a4fa529a243e5
Depends on D9942
Test Plan: ninja
Reviewers: #bitcoin_abc, majcosta
Reviewed By: #bitcoin_abc, majcosta
Differential Revision: https://reviews.bitcoinabc.org/D9943