test: fixes

Author: JoshuaKGoldberg

lib/utils.js

@@ -927,6 +927,10 @@ module.exports = {
   },
 
   getMetaSchemaNodeProperty(schemaNode, scopeManager) {
+    if (!schemaNode) {
+      return null;
+    }
+
     let { value } = schemaNode;
     if (value.type === 'Identifier' && value.name !== 'undefined') {
       const variable = findVariable(