wallet: Remove unused boost::this_thread::interruption_point #17405

BerkeleyEnvironment::Open is only called from the main thread (init) or an http rpc thread, neither of which can be interrupted, so remove the useless interruption point.

BerkeleyEnvironment{} is only used in tests, which run in a single process/thread, so remove the useless interruption point.

Also, interruption points are supposed to be called in loops for long operations, not one at the beginning of constructors. This was very strange.

ACK fad1de66a29bf6bd348a932150dad7d472feb3d0

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #17410 (Rename db log category to walletdb (like coindb) by laanwj)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

ACK fad1de66a29bf6bd348a932150dad7d472feb3d0