VerifyEnvironment and VerifyDatabaseFile were removed in D8617/[[https://github.com/bitcoin/bitcoin/pull/19324 | PR19324]], but their declarations weren't. Remove those.
This is a backport of [[https://github.com/bitcoin/bitcoin/pull/19457 | core#19457]] [3/3]
https://github.com/bitcoin/bitcoin/pull/19457/commits/0e279fe4899beae8630264ef1fe420dd71f29d5d