Support a scope property when the OAuth2 client is registered dynamically

[sberyozkin]

OAuth2 flow tab has a scope property, perhaps its value can be passed along with the dynamic client registration request. Otherwise the providers may associate a set of default scopes with the client. The same scope property value may also likely have to be included in the redirect to the provider.

For example, if I use an OAuth2 Flow client id option, with the configured scope, I can get a token containing an extra info related to these scopes.

With the dynamic client reg, I get a token with a very limited set of default claims