Support for @derivedFrom field on an interface

Do you want to request a feature or report a bug?
Feature

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem.
The following schema throws an error:

interface Owner {
  id: ID!
}

type Pool implements Owner @entity {
  id: ID! # Contract address
  loanPositions: [LoanPosition!] @derivedFrom(field: "owner")
}

type User implements Owner @entity {
  id: ID! # ethereum address
  loans: [Loan!] @derivedFrom(field: "borrower") # Loans, created by the user
  loanPositions: [LoanPosition!] @derivedFrom(field: "owner")
}

type LoanPosition @entity {
  id: ID!
  owner: Owner!
  loan: Loan!
}

Error:
✖ Failed to deploy to Graph node http://localhost:8020/: subgraph validation error: [SchemaValidationError([InvalidDerivedFrom("Pool", "loanPositions", "field owneron typeLoanPosition must have one of the following types: Pool, Pool!, [Pool!], [Pool!]!")])]