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:4021)
	at org.hl7.fhir.igtools.publisher.Publisher.loadConformance(Publisher.java:3927)
	at org.hl7.fhir.igtools.publisher.Publisher.createIg(Publisher.java:897)
	at org.hl7.fhir.igtools.publisher.Publisher.execute(Publisher.java:752)
	at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:8664)
	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:8461)