feat: oauth2-redirect accept flow in snake case

[fMeow]

Description

Some oauth2 or openIdConnect servers redirect back with flow name in snake case. The previous code accepts only flow name in camel case like accessCode or authorizationCode, but some oauth2 servers just use authorization_code.

Motivation and Context

Case mismatch fails openId (OAuth2, authorization_code) authorizations.

How Has This Been Tested?

Tested with both npm run start, and npm run build then tested with docker.

Screenshots (if appropriate):

From the https://editor.swagger.io/ website when I went through openId (OAuth2, authorization_code), with openid served by latest keycloak:

After this commit, tested in both local dev and docker:

Checklist

My PR contains...

• No code changes (src/ is unmodified: changes to documentation, CI, metadata, etc.)
• Dependency changes (any modification to dependencies in package.json)
• Bug fixes (non-breaking change which fixes an issue)
• Improvements (misc. changes to existing features)
• Features (non-breaking change which adds functionality)

My changes...

• are breaking changes to a public API (config options, System API, major UI change, etc).
• are breaking changes to a private API (Redux, component props, utility functions, etc.).
• are breaking changes to a developer API (npm script behavior changes, new dev system dependencies, etc).
• are not breaking changes.

Documentation

• My changes do not require a change to the project documentation.
• My changes require a change to the project documentation.
• If yes to above: I have updated the documentation accordingly.

Automated tests

• My changes can not or do not need to be tested.
• My changes can and should be tested by unit and/or integration tests.
• If yes to above: I have added tests to cover my changes.
• If yes to above: I have taken care to cover edge cases in my tests.
• All new and existing tests passed.