Relational models `saving relations` example is broken

[david-mcafee]

Describe the content issue:
A clear and concise description of what the content issue is. Is there content missing or is there incorrect content?
See the following updated schema as described in the docs:

enum PostStatus {
  ACTIVE
  INACTIVE
}

type Post @model {
  id: ID!
  title: String!
  rating: Int!
  status: PostStatus!
  # New field with @hasMany
  comments: [Comment] @hasMany(indexName: "byPost", fields: ["id"])
}

# New model
type Comment @model {
  id: ID!
  postID: ID! @index(name: "byPost")
  post: Post! @belongsTo(fields: ["postID"])
  content: String!
}

You’ll notice that Comment has a required postID, as well as a required post. This means when we save the Comment, both the instance and postID are required.

As of now, if a customer uses the code samples in the docs with this schema, they’ll get type errors (i.e. that postId is required when using this code example).

URL page where content issue is:
https://docs.amplify.aws/lib/datastore/relational/q/platform/js/#saving-relations