fix(DataStore): owner based auth, read operations

[wooj2]

In attempts to fix:
#691

Corresponding android change:
https://github.com/aws-amplify/amplify-android/pull/807/files#diff-5a6612b4d7b74db7c28a89d55c63cd09

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[wooj2]

There seems to be an issue with using a model like:

 type ModelMultipleOwner @model
   @auth(rules: [
     { allow: owner },
     { allow: owner, ownerField: "editors", operations: [update, read] }
   ]) {
   id: ID!
   content: String
   editors: [String]
 }

That being said, this is already an issue in our current codebase, and the code proposed in this PR doesn't make this issue worse.

[lawmicha]

FYI there are also some API integration tests that needs to be updated here https://github.com/aws-amplify/amplify-ios/tree/main/AmplifyPlugins/API/AWSAPICategoryPluginIntegrationTests/GraphQL/GraphQLWithUserPoolIntegrationTests/AuthDirective

but i'm guessing these will be vastly improved later anyways on the work you are doing for auth directive support