Update muted-tests.yml

Author: kkrik-es

muted-tests.yml

@@ -346,15 +346,6 @@ tests:
 - class: org.elasticsearch.reservedstate.service.FileSettingsServiceTests
   method: testProcessFileChanges
   issue: https://github.com/elastic/elasticsearch/issues/115280
-- class: org.elasticsearch.backwards.MixedClusterClientYamlTestSuiteIT
-  method: test {p0=indices.create/20_synthetic_source/object with unmapped fields}
-  issue: https://github.com/elastic/elasticsearch/issues/115910
-- class: org.elasticsearch.backwards.MixedClusterClientYamlTestSuiteIT
-  method: test {p0=indices.create/20_synthetic_source/empty object with unmapped fields}
-  issue: https://github.com/elastic/elasticsearch/issues/115911
-- class: org.elasticsearch.backwards.MixedClusterClientYamlTestSuiteIT
-  method: test {p0=indices.create/20_synthetic_source/nested object with unmapped fields}
-  issue: https://github.com/elastic/elasticsearch/issues/115912
 
 # Examples:
 #