KERML11 — Occurrences::surroundedByOccurrences::surroundingSpace should not be an end feature

In the Kernel Semantic Library model Occurrences, the feature Occurrence::surroundedByOccurrences has a single nested end feature

end [1] feature surroundingSpace: Occurrence subsets self;

However, the cross multiplicity is invalid here, because constraint validateCrossSubsettingCrossFeature requires that the owningType of an end feature with an owned cross feature have at least two ends. Indeed, it is not clear why this feature should be an end feature at all.