Fix Blake2b hash

[terryquigleysas]

Description

• Bug fix
• Blake2b is deterministic. Passing the parameters incorrectly results in the wrong hash being produced.
• What is the old behavior before changes and new behavior after changes?
  This may be considered a "Breaking Change" for 3.0.0 as the hashes will now be different - correct, but different from before.

Issues Resolved

Resolves #4274

Testing

Updated existing tests.
Ran Bulk Integration Test action against the branch.
Local testing.

Check List

• New functionality includes testing
• New functionality has been documented
• New Roles/Permissions have a corresponding security dashboards plugin PR
• API changes companion pull request created
• Commits are signed per the DCO using --signoff

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[nibix]

Note: In a mixed cluster state, this will yield inconsistent results: Some nodes will hash value A to hash X, while other nodes will hash value A to hash Y. This will especially affect aggregations. Are we okay with this (genuine question)? In any case, this should be documented.