[Process] Fix conflicts between latest 2.3 fix and 2.5 deprecation

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT

As reported in https://github.com/symfony/symfony/pull/10932#issuecomment-43939786, it's been introduced when merging 2.3 in master