TenantRead's attributes could support generic type

[Akkuma]

• I'm submitting a ...
  [ ] bug report
  [X] feature request
  [ ] question about the decisions made in the repository
  [ ] question about how to use this project

• Summary
  TenantRead's attributes are typed as object. This isn't very useful. It would be beneficial to be able to type the attributes. This could be done in a backward compatible way as well.

interface TenantRead<Attributes = object> {
  attributes?: Attributes
}

• Other information (e.g. detailed explanation, stack traces, related issues, suggestions how to fix, links for us to have context, eg. StackOverflow, personal fork, etc.)