Set project routing to null for now

Author: pawankartik-elastic

server/src/main/java/org/elasticsearch/action/search/TransportSearchAction.java

@@ -1104,6 +1104,7 @@ Map<String, SearchShardsResponse> createFinalResponse() {
                         // We do not use the relaxed index options here when validating indices' existence.
                         ElasticsearchException validationEx = CrossProjectIndexResolutionValidator.validate(
                             originalIdxOpts,
+                            null,
                             originResolvedIdxExpressions,
                             resolvedIndexExpressions
                         );