symfony

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #10849).

Discussion
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[WIP][Finder] Fix wrong implementation on sortable callback comparator

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | no

Working on this issue, i find SORT_BY_ACCESSED_TIME, SORT_BY_CHANGED_TIME, SORT_BY_MODIFIED_TIME was not tested.

- [x] Add test for SORT_BY_ACCESSED_TIME case
- [x] Add test for SORT_BY_CHANGED_TIME case
- [x] add test for SORT_BY_MODIFIED_TIME case

Commits
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b965fa23 [WIP][Finder] Fix wrong implementation on sortable callback comparator