OAuth 2: Variable expansion in scope aliases

[inseroaj]

Is your feature request related to a problem? Please describe.

As described in OAuth2 Topic Exchange Scopes it is possible to use variable expansion in scopes, like rabbitmq.write:*/x-{vhost}-*.
However, it seems this is not working/supported in Scope Aliases.
Addition of this feature would make it easy to apply user-based permissions with a single fixed scope.

Describe the solution you'd like

Consider a token including the scope MYSCOPE.
Using a scope alias, the read permission can be set with
auth_oauth2.scope_aliases.MYSCOPE = rabbitmq.read:*/queueprefix.{sub}.*
This would cause a user with subject MYUSER and scope MYSCOPE to have read access to queues named queueprefix.MYUSER.*.

Describe alternatives you've considered

No response

Additional context

No response

[MarcialRosales]

@inseroaj Indeed, this feature was initially added exclusively when checking permission on topics as it is stated in the docs.