java.lang.NullPointerException
	at org.hl7.fhir.r5.comparison.ValueSetComparer.findInList(ValueSetComparer.java:196)
	at org.hl7.fhir.r5.comparison.ValueSetComparer.compareCompose(ValueSetComparer.java:139)
	at org.hl7.fhir.r5.comparison.ValueSetComparer.compare(ValueSetComparer.java:128)
	at org.hl7.fhir.r5.comparison.ComparisonSession.compare(ComparisonSession.java:87)
	at org.hl7.fhir.igtools.publisher.PreviousVersionComparator.finishChecks(PreviousVersionComparator.java:252)
	at org.hl7.fhir.igtools.publisher.Publisher.checkConformanceResources(Publisher.java:4009)
	at org.hl7.fhir.igtools.publisher.Publisher.loadConformance(Publisher.java:3915)
	at org.hl7.fhir.igtools.publisher.Publisher.createIg(Publisher.java:890)
	at org.hl7.fhir.igtools.publisher.Publisher.execute(Publisher.java:745)
	at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:8561)
	at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.runBuild(PublicationProcess.java:342)
	at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.doPublish(PublicationProcess.java:241)
	at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.publishInner(PublicationProcess.java:190)
	at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.publish(PublicationProcess.java:60)
	at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:8358)