The Teiid model deriver is not being used

The org.overlord.sramp.integration.teiid.deriver.ModelDeriverProvider class is not providing the correct deriver. I think this class was copy/pasted and never changed to return the correct provider type.

I think we just need to change from this:

        return Collections.singletonMap(TeiidArtifactType.MODEL.extendedType(), (ArtifactDeriver)new VdbManifestDeriver());

to this:

        return Collections.singletonMap(TeiidArtifactType.MODEL.extendedType(), (ArtifactDeriver)new ModelDeriver());