org.hl7.fhir.exceptions.DefinitionException: Found a slice at 'Immunization.performer' but there was no definition for the slicing
	at org.hl7.fhir.services.utilities.DefinitionNavigator.loadChildren(DefinitionNavigator.java:253)
	at org.hl7.fhir.services.utilities.DefinitionNavigator.children(DefinitionNavigator.java:167)
	at org.hl7.fhir.services.comparison.StructureDefinitionComparer.compareDiffChildren(StructureDefinitionComparer.java:565)
	at org.hl7.fhir.services.comparison.StructureDefinitionComparer.compareDiff(StructureDefinitionComparer.java:470)
	at org.hl7.fhir.services.comparison.StructureDefinitionComparer.compare(StructureDefinitionComparer.java:166)
	at org.hl7.fhir.services.comparison.ComparisonSession.compare(ComparisonSession.java:93)
	at org.hl7.fhir.igtools.publisher.comparators.PreviousVersionComparator.finishChecks(PreviousVersionComparator.java:269)
	at org.hl7.fhir.igtools.publisher.PublisherProcessor.checkConformanceResources(PublisherProcessor.java:1516)
	at org.hl7.fhir.igtools.publisher.PublisherProcessor.loadConformance2(PublisherProcessor.java:109)
	at org.hl7.fhir.igtools.publisher.Publisher.createIg(Publisher.java:397)
	at org.hl7.fhir.igtools.publisher.Publisher.execute(Publisher.java:226)
	at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:1625)