Fixed PIM-3194

| Q                    | A
| -------------------- | ---
| Bug fix?             | Yes
| New feature?         | No 
| BC breaks?           | No
| CI currently passes? | ?
| Tests pass?          | Yes
| Scenarios pass?      | Yes
| Checkstyle issues?*  | No
| PMD issues?**        | No
| Changelog updated?   | Yes
| Fixed tickets        | PIM-3194
| DB schema updated?   | No
| Migration script?    | No
| Doc PR               | No

This is needed for the FeuVert DAM. It fixes entities collections being reordered on hydration.
A proper foreach would be cleaner.