[backport#15588 2/3] Log the actual wallet file version

Summary:
The actual wallet file version is the minversion record, not the
version record.

https://github.com/bitcoin/bitcoin/pull/15588/commits/b3d4f6c9619142948ab3d53551b4f3c0d7d73bde

Depends on D7017

Partial backport of Core PR15588

Test Plan:

ninja check

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D7018