[BUG] - rdfs:Literal is a valid OWL2 datatype

[NicolasRouquette]

Description

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rdfs:Literal is included in the list of IRIs in section 2.4: https://www.w3.org/TR/owl2-syntax/#IRIs

Furthermore, the datatype section explicitly refers to rdfs:Literal: https://www.w3.org/TR/owl2-syntax/#Datatypes

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Expected Behavior

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[melaasar]

I added rdfs:Literal to the rdfs ontology:
https://github.com/opencaesar/core-vocabularies/blob/159faeca9f10a7078b5efa08ef79b526f980d38a/src/oml/www.w3.org/2000/01/rdf-schema.oml#L17