Follow-up from "Add NuGet package tags support"

The following discussion from !30726 (merged) should be addressed:

• @mayra-cabrera started a discussion:

  We could use package_file.package_id instead of fetching package and then selecting the id:

  [8] pry(main)> package_file = Packages::PackageFile.last
    Packages::PackageFile Load (0.5ms)  SELECT "packages_package_files".* FROM "packages_package_files" ORDER BY "packages_package_files"."id" DESC LIMIT 1
  => #<Packages::PackageFile:0x00007f8be401ce90
   id: 25,
   package_id: 25,
   created_at: Tue, 07 Apr 2020 23:13:43 UTC +00:00,
   updated_at: Tue, 07 Apr 2020 23:13:43 UTC +00:00,
   size: 6,
   file_store: 1,
   file_md5: nil,
   file_sha1: "f572d396fae9206628714fb2ce00f72e94f2258f",
   file_name: "@flightjs/npm_package_4-1.12.4.tgz",
   file: "@flightjs/npm_package_4-1.12.4.tgz",
   file_sha256: nil,
   verification_retry_at: nil,
   verified_at: nil,
   verification_checksum: nil,
   verification_failure: nil,
   verification_retry_count: nil>
  [9] pry(main)> package_file.package_id
  => 25
  [10] pry(main)> package_file.package.id
    Packages::Package Load (8.5ms)  SELECT "packages_packages".* FROM "packages_packages" WHERE "packages_packages"."id" = 25 LIMIT 1
  => 25