SLING-8351 enable reregisterExisting when registering node type definitions
diff --git a/core/src/main/java/org/apache/sling/testing/mock/sling/NodeTypeDefinitionScanner.java b/core/src/main/java/org/apache/sling/testing/mock/sling/NodeTypeDefinitionScanner.java
index 55287e9..63ed2ed 100644
--- a/core/src/main/java/org/apache/sling/testing/mock/sling/NodeTypeDefinitionScanner.java
+++ b/core/src/main/java/org/apache/sling/testing/mock/sling/NodeTypeDefinitionScanner.java
@@ -203,7 +203,7 @@
             }
             try {
                 Reader reader = new InputStreamReader(is);
-                CndImporter.registerNodeTypes(reader, nodeTypeResource, nodeTypeManager, namespaceRegistry, valueFactory, false);
+                CndImporter.registerNodeTypes(reader, nodeTypeResource, nodeTypeManager, namespaceRegistry, valueFactory, true);
                 nodeTypeResourcesIterator.remove();
             }
             catch (Throwable ex) {