Pad only when necessary.

The store will add extra META_SIZE padding even when there's no need for the pad (e.g. empty commit). Also because we already have bcrypto for bench as devDependency, we can use it for the tests as well.

Pull Request Test Coverage Report for Build 2904049817

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This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 5 of 5 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+1.6%) to 70.485%

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Totals
Change from base Build 2515224032:	1.6%
Covered Lines:	1817
Relevant Lines:	2385

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💛 - Coveralls

Maybe we should also make FILE_SIZE divisible by 38 (META_SIZE) because that could also lead to incorrect offset for the findMeta.