Snyk's OAuth implementation is capable of indicating the environment
which the user is authenticated into and authorized to access.

This is specified in the audience JWT claim ("aud"). Snyk's
implementation of this claim contains an array of strings, per RFC 7519.

If set and non-empty, the first audience URL is taken as the default API
URL that the client should use, unless the endpoint was specifically
configured.

It's a test JWT created on jwt.io for testing the parsing of claims
and cannot be used as a valid authorization anywhere.

If an instance parameter is provided in the redirect, use it to modify
the URL from where the oauth token is obtained.

The instance provided is the Snyk region domain, minus the api. host
prefix.