[Validator] Replaced inexistent interface

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | no
| Fixed tickets | #9631
| License       | MIT
| Doc PR        | -

`ClassMetadataFactoryInterface` was removed in 2.3 (#6096) and replaced with `MetadataFactoryInterface`.