[chapter 5] fix User inPhotos logic

[dorakemon]

I read Japanese edition and found a mistake that is not related to a main topic

The below code is written in a book

    inPhotos: (parent: any) =>
      tags
        .filter((tag) => tag.userID === parent.id)
        .map((tag) => tag.photoID)
        .map((photoID) => photos.find((p) => p.id === photoID))

However correct code is below

    inPhotos: (parent: any) =>
      tags
        // NOT parent.id BUT parent.githubLogin
        .filter((tag) => tag.userID === parent.githubLogin)
        .map((tag) => tag.photoID)
        .map((photoID) => photos.find((p) => p.id === photoID))

tag.userID is githubLogin ("gPlake") NOT id ("1")