Fixed the relaxed constraints

Author: mridula-s109

test/framework/src/main/java/org/elasticsearch/search/retriever/TestRetrieverBuilder.java

@@ -50,7 +50,6 @@ public static TestRetrieverBuilder createRandomTestRetrieverBuilder() {
 
     public static final ConstructingObjectParser<TestRetrieverBuilder, RetrieverParserContext> PARSER = new ConstructingObjectParser<>(
         NAME,
-        true, // ignore unknown fields
         args -> new TestRetrieverBuilder((String) args[0])
     );
 

x-pack/plugin/rank-rrf/src/main/java/org/elasticsearch/xpack/rank/rrf/RRFRetrieverBuilder.java

@@ -69,7 +69,7 @@ public final class RRFRetrieverBuilder extends CompoundRetrieverBuilder<RRFRetri
     @SuppressWarnings("unchecked")
     static final ConstructingObjectParser<RRFRetrieverBuilder, RetrieverParserContext> PARSER = new ConstructingObjectParser<>(
         NAME,
-        true, // Set to true to ignore unknown fields
+        false,
         args -> {
             List<RRFRetrieverComponent> retrieverComponents = args[0] == null ? List.of() : (List<RRFRetrieverComponent>) args[0];
             List<String> fields = (List<String>) args[1];