NIFI-7332 Added method to log available claim names from the ID provi…

[mtien-apache]

…der response when the OIDC Identifying User claim is not found. Revised log message to print available claims.

Added new StandardOidcIdentityProviderGroovyTest file.
Updated deprecated methods in StandardOidcIdentityProvider. Changed log output to print all available claim names from JWTClaimsSet. Added unit test.
Fixed typos in NiFi Docs Admin Guide.
Refactored exchangeAuthorizationCode method. Added unit tests.
Refactored code. Added unit tests.
Refactored OIDC provider to decouple constructor & network-dependent initialization.
Refactored OIDC provider to separately authorize the client. Added unit tests.

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Added method to log available claims from ID provider response when the OIDC Identifying User claim is not found. Refactored StandardOidcIdentityProvider class and added unit tests.

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[alopresto]

It looks like the internal methods in the identity provider were refactored to make this separate, but exchangeAuthorizationCode is still the only public method, while the others are still private. Maybe translate the change to here as well.

[mtien-apache]

@alopresto I have separated the authorization from exchangeAuthorizationCode.

[thenatog]

Reviewing..

[thenatog]

Tested with G Suite OIDC provider, and ran a contrib check. All checks passing. +1. Will merge.

[thenatog]

Also, thank you for these changes, it should help with some work I am doing in NiFi Registry.

[kevdoran]

Thanks for the contribution @mtien-apache, and for the reviews @thenatog, @alopresto. I cherry-picked this to main.