[dev-lunatic-v2] Usage of `LabelType` in `ConditionFilterType`?

The `LabelType` has been introduced to replace String labels by an object that contains metadata about the concerned language (VTL / MD). This object is not used in the `ConditionFilterType`, which seems a bit odd.

I suggest something like this:

https://github.com/InseeFr/Lunatic-Model/blob/dev-lunatic-v2/src/main/resources/xsd/LunaticModelFlat.xsd#L85

```xsd






```

https://github.com/InseeFr/Lunatic-Model/blob/dev-lunatic-v2/src/main/resources/xsd/LunaticModel.xsd#L92

```xsd






```

Note:

These changes could also affect the "json-cleaner.xsl" script:

https://github.com/InseeFr/Lunatic-Model/blob/dev-lunatic-v2/src/main/resources/xslt/json-cleaner.xsl

and [Eno](https://github.com/InseeFr/Eno/tree/main)'s branch [dev-lunatic-v2](https://github.com/InseeFr/Eno/tree/dev-lunatic-v2)

https://github.com/InseeFr/Eno/blob/dev-lunatic-v2/src/main/resources/xslt/transformations/ddi2lunatic-xml/ddi2lunatic-xml-fixed.xsl#L739