Missing otp parameter in tokenParams

[psamim]

Describe the problem

According to the documentation at https://auth0.com/docs/api/authentication?http#authenticate-user the /oauth/token end-point accepts otp parameter. But this parameter is missing in the white-list in https://github.com/auth0/auth0.js/blob/master/src/helper/parameters-whitelist.js#L8 . So the oauthToken cannot white-list the otp parameter and removes it in https://github.com/auth0/auth0.js/blob/master/src/authentication/index.js#L397 .

What was the expected behavior?

To include the otp param and have it white-listed.

Reproduction

outh0.oauthToken({ username, otp, realm, grantType, audience });

Will result in error:

missing required parameter otp

Environment

Latest version from master branch