Add organization option in query params

[jhiner]

Description

As a part of shipping SAML support for Organizations, I was using my fork of this library to test. I offer this PR because I think it'll be useful for customers (and our internal use) when we ship that feature.

If you pass organization in the options to passport, it will be sent in the query string when submitting the SAMLRequest.

References

N/A

Testing

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have added documentation for new/changed functionality in this PR or in auth0.com/docs
• All active GitHub checks for tests, formatting, and security are passing
• The correct base branch is being used, if not master

[6footgeek]

LGTM + ive been using the previous fork of this for ages.
+1