Mute org.elasticsearch.xpack.ml.integration.ClassificationIT testDependentVariableIsNested elastic#121458

Author: elasticsearchmachine

muted-tests.yml

@@ -545,3 +545,6 @@ tests:
 - class: org.elasticsearch.smoketest.DocsClientYamlTestSuiteIT
   method: test {yaml=reference/rest-api/common-options/line_102}
   issue: https://github.com/elastic/elasticsearch/issues/121748
+- class: org.elasticsearch.xpack.ml.integration.ClassificationIT
+  method: testDependentVariableIsNested
+  issue: https://github.com/elastic/elasticsearch/issues/121458