Refactor: Move passwordless "invalid credentials" errors

[lbalmaceda]

Changes

On the last patch we released support for catching additional Passwordless error messages that were missing from this SDK. However, we realized that the method in which those were added was not quite right, as it corresponded to MFA flows. This PR changes that and moves the new error handling into a proper method for invalid credentials.

TLDR

If you were using version 1.29.1 to catch Passwordless invalid code errors, you will need to update your code:

-boolean invalidInput = err.isMultifactorCodeInvalid()
+boolean invalidInput = err.isInvalidCredentials()

References

This rollbacks the changes introduced in #371, but keeps them in a separate method.

• https://github.com/auth0/Auth0.Android/releases/tag/1.29.1

Testing

Please describe how this can be tested by reviewers. Be specific about anything not tested and reasons why. Since this library has unit 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 the platform/language or why not

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