deprecate the restful API of batch ingestion (#3688)

Signed-off-by: Xun Zhang <xunzh@amazon.com>

Author: Zhangxunmt

plugin/src/main/java/org/opensearch/ml/plugin/MachineLearningPlugin.java

@@ -233,7 +233,6 @@
 import org.opensearch.ml.processor.MLInferenceSearchRequestProcessor;
 import org.opensearch.ml.processor.MLInferenceSearchResponseProcessor;
 import org.opensearch.ml.repackage.com.google.common.collect.ImmutableList;
-import org.opensearch.ml.rest.RestMLBatchIngestAction;
 import org.opensearch.ml.rest.RestMLCancelBatchJobAction;
 import org.opensearch.ml.rest.RestMLCreateConnectorAction;
 import org.opensearch.ml.rest.RestMLCreateControllerAction;
@@ -828,7 +827,6 @@ public List<RestHandler> getRestHandlers(
         RestMLListToolsAction restMLListToolsAction = new RestMLListToolsAction(toolFactories);
         RestMLGetToolAction restMLGetToolAction = new RestMLGetToolAction(toolFactories);
         RestMLGetConfigAction restMLGetConfigAction = new RestMLGetConfigAction(mlFeatureEnabledSetting);
-        RestMLBatchIngestAction restMLBatchIngestAction = new RestMLBatchIngestAction();
         RestMLCancelBatchJobAction restMLCancelBatchJobAction = new RestMLCancelBatchJobAction();
         return ImmutableList
             .of(
@@ -883,7 +881,6 @@ public List<RestHandler> getRestHandlers(
                 restMLListToolsAction,
                 restMLGetToolAction,
                 restMLGetConfigAction,
-                restMLBatchIngestAction,
                 restMLCancelBatchJobAction
             );
     }