If we're constructing the SafeDbt without provided data, it is always malloced,
so that is the case we expose.
Also run clang-format.
https://github.com/bitcoin/bitcoin/pull/14268/commits/4a86a0acd9ac3ca392f0584a5fd079a856e5e4ba#
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Depends on D7322
Concludes backport of Core [[https://github.com/bitcoin/bitcoin/pull/14268 | PR14268]]