[SDK-4014] User Authentication Method management API support

[stevehobbsdev]

Changes

This PR adds support for the User Authentication Method endpoints in the Auth0 management API.

Endpoint	Description
GET /api/v2/users/{user_id}/authentication-methods	Get all authentication methods for a user
GET /api/v2/users/{user_id}/authentication-methods/{id}	Get an authentication method for a user by ID
POST /api/v2/users/{user_id}/authentication-methods	Create a new authentication method for a user
PUT /api/v2/users/{user_id}/authentication-methods	Update all authentication methods
PATCH /api/v2/users/{user_id}/authentication-methods/{id}	Update one authentication method for a user by ID
DELETE /api/v2/users/{user_id}/authentication-methods	Delete all authentication methods for a user
DELETE /api/v2/users/{user_id}/authentication-methods/{id}	Delete one authentication method for a user by ID

References

SDK-4014

Testing

Please describe how this can be tested by reviewers. Be specific about anything not tested and reasons why. If this library has unit and/or integration testing, tests should be added for new functionality and existing tests should complete without errors.

• This change adds unit test coverage
• This change adds integration test coverage
• This change has been tested on the latest version of Ruby

Checklist

• I have read the Auth0 general contribution guidelines
• I have read the Auth0 Code of Conduct
• All existing and new tests complete without errors
• Rubocop passes on all added/modified files
• All active GitHub checks have passed