Create a Join Flow. A Flow combines configurations for one or more vendors that may be used
to allow system owners to grant authorization for systems they control. Flows are reusable
across multiple authorization sessions.

Upon completion of a session for this Flow, a redirect to the given redirectURI will be served.
The redirect URI will receive a state query string parameter matching the state parameter
that was provided when the session was initiated via the /join/flows/{flowID}/authorize endpoint.

Upon success, the redirect URI will also receive one or more enrollmentID query string
parameters, if the Flow was associated with a Program. Most vendors create a single Enrollment
per authorization session, resulting in a single enrollmentID parameter, but some vendors
may allow a system owner to select multiple devices in one session, resulting in multiple
enrollmentID parameters (one per created Enrollment) being appended to the redirect URI's
query string.

Upon failure, the redirect URI will receive an error query string parameter
with an OAuth error code and an optional
error_description parameter with a description of the error.

Flows may be deleted, but are immutable after creation.

See the Working with Production Devices guide for more context on usage of this API.