PIM-2225 Allow registration of many custom serializer

| Q                   | A
| ------------------- | ---
| Bug fix?            | no
| New feature?        | yes
| BC breaks?          | no
| Tests pass?         | yes
| Scenarios pass?     | yes
| Checkstyle issues?  | no
| Changelog updated?  | no
| Fixed tickets       | PIM-2225
| Doc PR              |

They all can get their own normalizers and encoders.
Particularly useful to inject a doctrine repository inside a normalizer
as the pim_serializer service is inject inside the version_manager which
is used by a doctrine event_listener (thus creating a circular
reference)