Needed to set mock times, and get wallet interface pointers correctly when
wallet code is running in a different process from node code.
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https://github.com/bitcoin/bitcoin/pull/17999/commits/1dde238f2c21a0cc9bada10a2449cf9c6b2178ad
Partial backport of Core [[https://github.com/bitcoin/bitcoin/pull/17999 | PR17999]]