**Found in version**
- Observed in 8.2.3, but might exist longer

**Steps to reproduce**
On a multi node cloud cluster (might also work on a local multi node cluster):
- Create a transform with a retention policy
- Update the transform and remove the retention policy

**Expected result**
- The retention policy is removed

**Actual result**
- This sometimes results in an error:
```
An error occurred calling the API endpoint to update transforms.
Bad Request: [illegal_argument_exception: [illegal_argument_exception] Reason: 
Unknown NamedWriteable [org.elasticsearch.xpack.core.transform.transforms.RetentionPolicyConfig][null_retention_policy]]:
Unknown NamedWriteable [org.elasticsearch.xpack.core.transform.transforms.RetentionPolicyConfig][null_retention_policy]
```

**Additional information**
- Quote from slack discussion with @benwtrent:
  > It wouldn’t happen if you hit a node that can execute the update immediately without serializing to a different node
x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/XPackClientPlugin.java
import org.elasticsearch.xpack.core.ml.action.DeleteForecastAction;
import org.elasticsearch.xpack.core.ml.action.DeleteJobAction;
import org.elasticsearch.xpack.core.ml.action.DeleteModelSnapshotAction;
import org.elasticsearch.xpack.core.ml.action.DeleteTrainedModelAction;
import org.elasticsearch.xpack.core.ml.action.EvaluateDataFrameAction;
import org.elasticsearch.xpack.core.ml.action.ExplainDataFrameAnalyticsAction;
import org.elasticsearch.xpack.core.ml.action.FinalizeJobExecutionAction;
import org.elasticsearch.xpack.core.ml.action.FlushJobAction;
import org.elasticsearch.xpack.core.ml.action.ForecastJobAction;
import org.elasticsearch.xpack.core.ml.action.GetBucketsAction;
import org.elasticsearch.xpack.core.ml.action.GetCalendarEventsAction;
import org.elasticsearch.xpack.core.ml.action.GetCalendarsAction;
import org.elasticsearch.xpack.core.ml.action.GetCategoriesAction;
import org.elasticsearch.xpack.core.ml.action.GetDataFrameAnalyticsAction;
import org.elasticsearch.xpack.core.ml.action.GetDataFrameAnalyticsStatsAction;
import org.elasticsearch.xpack.core.ml.action.GetDatafeedsAction;
import org.elasticsearch.xpack.core.ml.action.GetDatafeedsStatsAction;
import org.elasticsearch.xpack.core.ml.action.GetFiltersAction;
import org.elasticsearch.xpack.core.ml.action.GetInfluencersAction;
import org.elasticsearch.xpack.core.ml.action.GetJobsAction;
import org.elasticsearch.xpack.core.ml.action.GetJobsStatsAction;
import org.elasticsearch.xpack.core.ml.action.GetModelSnapshotsAction;
import org.elasticsearch.xpack.core.ml.action.GetOverallBucketsAction;
import org.elasticsearch.xpack.core.ml.action.GetRecordsAction;
import org.elasticsearch.xpack.core.ml.action.GetTrainedModelsAction;
import org.elasticsearch.xpack.core.ml.action.GetTrainedModelsStatsAction;
import org.elasticsearch.xpack.core.ml.action.InferModelAction;
import org.elasticsearch.xpack.core.ml.action.IsolateDatafeedAction;
import org.elasticsearch.xpack.core.ml.action.KillProcessAction;
import org.elasticsearch.xpack.core.ml.action.MlInfoAction;