[Feedback] Text Updates needed on documentation

**Page**: [`/cli/graphql/data-modeling`](https://docs.amplify.aws/cli/graphql/data-modeling)

**Feedback**:
lines from document:
const result = await API.graphql(graphqlOperation(getPost, { id: post.id }));
const postWithComments = result.data.createPost;
const postComments = postWithComments.comments.items; // access comments from post

Feedback:
second line should be with getPost not createPost : const postWithComments = result.data.getPost;

another set of lines that repeats two times in the document:
"This generates queries and mutations that allow you to retrieve the related Comment records from the source Post record and vice versa:"

second time actually it is supposed to be Tag records and not Comment records. It was relationship beween Posts and Tags.