    org.hl7.fhir.exceptions.DefinitionException: Found a slice at 'Observation.category' but there was no definition for the slicing
    	at org.hl7.fhir.r5.utils.DefinitionNavigator.loadChildren(DefinitionNavigator.java:252)
    	at org.hl7.fhir.r5.utils.DefinitionNavigator.children(DefinitionNavigator.java:170)
    	at org.hl7.fhir.r5.comparison.StructureDefinitionComparer.compareDiffChildren(StructureDefinitionComparer.java:570)
    	at org.hl7.fhir.r5.comparison.StructureDefinitionComparer.compareDiff(StructureDefinitionComparer.java:475)
    	at org.hl7.fhir.r5.comparison.StructureDefinitionComparer.compare(StructureDefinitionComparer.java:179)
    	at org.hl7.fhir.r5.comparison.ComparisonSession.compare(ComparisonSession.java:107)
    	at org.hl7.fhir.igtools.publisher.comparators.PreviousVersionComparator.finishChecks(PreviousVersionComparator.java:267)
    	at org.hl7.fhir.igtools.publisher.PublisherProcessor.checkConformanceResources(PublisherProcessor.java:1491)
    	at org.hl7.fhir.igtools.publisher.PublisherProcessor.loadConformance2(PublisherProcessor.java:104)
    	at org.hl7.fhir.igtools.publisher.Publisher.createIg(Publisher.java:366)
    	at org.hl7.fhir.igtools.publisher.Publisher.execute(Publisher.java:218)
    	at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:1482)