Authn jwt refactor v4

[jvanderhoof]

Desired Outcome

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the original request that resulted in these code changes? Feel free to copy
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Implemented Changes

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Connected Issue/Story

Resolves #[relevant GitHub issue(s), e.g. 76]

CyberArk internal issue ID: [insert issue ID]

Definition of Done

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Changelog

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Test coverage

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  changes, or
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Documentation

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Behavior

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Security

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