Fixed RRF YAML REST Test: rrf with pinned retriever as a sub-retriever

muted-tests.yml

@@ -509,9 +509,6 @@ tests:
 - class: org.elasticsearch.qa.verify_version_constants.VerifyVersionConstantsIT
   method: testLuceneVersionConstant
   issue: https://github.com/elastic/elasticsearch/issues/125638
-- class: org.elasticsearch.xpack.rank.rrf.RRFRankClientYamlTestSuiteIT
-  method: test {yaml=rrf/950_pinned_interaction/rrf with pinned retriever as a sub-retriever}
-  issue: https://github.com/elastic/elasticsearch/issues/129845
 - class: org.elasticsearch.gradle.internal.InternalDistributionBwcSetupPluginFuncTest
   method: "builds distribution from branches via archives extractedAssemble [bwcDistVersion: 8.2.1, bwcProject: bugfix, expectedAssembleTaskName:
     extractedAssemble, #2]"

x-pack/plugin/rank-rrf/src/yamlRestTest/resources/rest-api-spec/test/rrf/950_pinned_interaction.yml

@@ -77,22 +77,15 @@ setup:
           retriever:
             rrf:
               retrievers:
-                -
-                  standard:
-                    query:
-                      match: { text: "document" }
                 -
                   pinned:
                     ids: ["doc4", "doc5"]
                     retriever:
                       standard:
                         query:
-                          match: { text: "document" }
-
-  - match: { hits.total.value: 5 }
-  - match: { hits.hits.0._id: doc1 }
-  - lt: { hits.hits.0._score: 100.0 }
-  - match: { hits.hits.1._id: doc4 }
-  - match: { hits.hits.2._id: doc5 }
+                          match_none: {}
 
+  - match: { hits.total.value: 2 }
+  - match: { hits.hits.0._id: doc4 }
+  - match: { hits.hits.1._id: doc5 }