doc: fix typos #31253

There are some typos in the code comments and use this change to update them

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Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/31253.

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Reviews

See the guideline for information on the review process. A summary of reviews will appear here.

Please squash your commits according to https://github.com/bitcoin/bitcoin/blob/master/CONTRIBUTING.md#squashing-commits

If your change contains a merge commit, the above workflow may not work and you will need to remove the merge commit first. See the next section for details on how to rebase.

The merge commit would need to be removed: https://github.com/bitcoin/bitcoin/blob/master/CONTRIBUTING.md#rebasing-changes

doc: recitfy typos

Also, there's a typo in the PR title. :)

Same as #30259?

Pulled this into another branch.