At BlockConnected/BlockDisconnected, we rely on height of block
itself to know current height of wallet
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https://github.com/bitcoin/bitcoin/pull/15931/commits/5aacc3eff15b9b5bdc951f1e274f00d581f63bce
Depends on D7506
Partial backport of Core [[https://github.com/bitcoin/bitcoin/pull/15931 | PR15931]]