PIM-3369: import products - couple channel/locale doesn't exist : import succeeds

| Q                    | A
| -------------------- | ---
| Bug fix?             | Y
| New feature?         | N
| BC breaks?           | N
| CI currently passes? | Y
| Tests pass?          | Y
| Scenarios pass?      | Y
| Checkstyle issues?*  | N
| PMD issues?**        | N
| Changelog updated?   | N
| Fixed tickets        | PIM-3369
| DB schema updated?   | N
| Migration script?    | N
| Doc PR               | N
So this is a core rule : identation should be like that : https://github.com/akeneo/pim-community-dev/blob/PIM-3368/spec/Pim/Bundle/TransformBundle/Transformer/AssociationTransformerSpec.php#L27