[ML] Disable security audit trail in native integ tests suite (#39683)

Investigating how to make DeleteExpiredDataIT faster, it was
revealed that the security audit trail threads were quite hot.
Disabling that seems to be helping quite a bit with making this
test faster. This commit also unmutes the test to see how it goes
with the audit trail disabled.

Relates #39658
Closes #39575

Author: dimitris-athanasiou

x-pack/plugin/ml/qa/native-multi-node-tests/build.gradle

@@ -44,7 +44,7 @@ integTestCluster {
     setting 'xpack.security.transport.ssl.key', nodeKey.name
     setting 'xpack.security.transport.ssl.certificate', nodeCert.name
     setting 'xpack.security.transport.ssl.verification_mode', 'certificate'
-    setting 'xpack.security.audit.enabled', 'true'
+    setting 'xpack.security.audit.enabled', 'false'
     setting 'xpack.license.self_generated.type', 'trial'
     setting 'xpack.ml.min_disk_space_off_heap', '200mb'
 

x-pack/plugin/ml/qa/native-multi-node-tests/src/test/java/org/elasticsearch/xpack/ml/integration/DeleteExpiredDataIT.java

@@ -91,7 +91,6 @@ public void testDeleteExpiredDataGivenNothingToDelete() throws Exception {
         client().execute(DeleteExpiredDataAction.INSTANCE, new DeleteExpiredDataAction.Request()).get();
     }
 
-    @AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/39575")
     public void testDeleteExpiredData() throws Exception {
         // Index some unused state documents (more than 10K to test scrolling works)
         BulkRequestBuilder bulkRequestBuilder = client().prepareBulk();