New iteration of MOD metadata review should cover sdo:DefinedTermSet

[jonquet]

Discussed in #51

^{Originally posted by jonquet September 19, 2023}
Since MOD 1.4 Schema.org (SDO) has added the notion of DefinedTerm and DefinedTermSet (another word for semantic artefact I believe).

We are going to need to review the metadata properties of this object.
Things inherited from CreativeWork and Thing were already integrated in MOD1.4 which assume an ontology was a sdo:Dataset

Note with respect to #34 => we might have a conflict when aligning our DCAT MOD2 approach with Schema.org.
@agbeltran : DCAT3 is aligned to sdo:DataSet and if we decide a mod:SemanticAretfact is a dcat:Dataset we are going to have an issue of alignement with Schema.org in which the relevant class is now sdo:DefinedTermSet which is disjoint from sdo:Dataset