Merge branch '22768-revert-to-touch-file-system' into 'master'

Revert to use Mounter method to check existence

## What does this MR do?

Revert a change on gitlab-ce that we never get into gitlab-ee due to spec failures and a lack of a proper solution. So we want to keep both repos in the same codebase about this.

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #22768

See merge request !6590

CHANGELOG

@@ -14,6 +14,7 @@ v 8.13.0 (unreleased)
   - Only update issuable labels if they have been changed
   - Revoke button in Applications Settings underlines on hover.
   - Fix Long commit messages overflow viewport in file tree
+  - Revert avoid touching file system on Build#artifacts?
   - Update ruby-prof to 0.16.2. !6026 (Elan Ruusamäe)
   - Fix unnecessary escaping of reserved HTML characters in milestone title. !6533
   - Add organization field to user profile

app/models/ci/build.rb

@@ -373,7 +373,7 @@ module Ci
     end
 
     def artifacts?
-      !artifacts_expired? && self[:artifacts_file].present?
+      !artifacts_expired? && artifacts_file.exists?
     end
 
     def artifacts_metadata?