Unmuting corrected test (elastic#127320)

Author: benwtrent

muted-tests.yml

@@ -345,9 +345,6 @@ tests:
 - class: org.elasticsearch.search.SearchWithRejectionsIT
   method: testOpenContextsAfterRejections
   issue: https://github.com/elastic/elasticsearch/issues/126340
-- class: org.elasticsearch.backwards.MixedClusterClientYamlTestSuiteIT
-  method: test {p0=search.vectors/42_knn_search_bbq_flat/Vector rescoring has same scoring as exact search for kNN section}
-  issue: https://github.com/elastic/elasticsearch/issues/126368
 - class: org.elasticsearch.smoketest.MlWithSecurityIT
   method: test {yaml=ml/start_data_frame_analytics/Test start classification analysis when the dependent variable cardinality is too low}
   issue: https://github.com/elastic/elasticsearch/issues/123200