AuthnJWT: support claims with hyphens

[john-odonnell]

Desired Outcome

AuthnJWT uses the regex ^[a-zA-Z|$|_][a-zA-Z|$|_|0-9|.](\/[a-zA-Z|$|_][a-zA-Z|$|_|0-9|.])*$ to validate token claims, and therefore does not support claims including hyphens. An example of a claim that fails this validation is CircleCI's additional token claims: oidc.circleci.com/project-id et al.

AuthnJWT also currently does not support claims with inline namespaces (namespace.com/claim-key), instead digesting slash-delimited claims as nested. The CircleCI example above still applies.

Implemented Changes

• Updated the regex to include hyphens as supported characters: ^[a-zA-Z|$|_][a-zA-Z|$|_|0-9|.](\/[a-zA-Z|$|_][a-zA-Z|$|_|\-|0-9|.])*$
• Update claim parsing to attempt to use the raw claim before decomposing it and searching for a nested claim.
• Update unit and integration tests for AuthnJWT input validation

Connected Issue/Story

ONYX-29842

Definition of Done

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[gl-johnson]

LGTM, although looks like it needs a fresh rebase

[codeclimate]

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[codeclimate]

Code Climate has analyzed commit d055458 and detected 1 issue on this pull request.

Here's the issue category breakdown:

Category	Count
Style	1

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 89.9% (-1.5% change).

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