The way, the CS batching in `TransportRolloverAction` is written is broken for large batches of tasks. Each task result will contain the cluster state after applying the task. This consumes unmanageable amounts of memory for large cluster states if a larger number of rollovers gets batched, causing master nodes to run out of heap from endless `RolloverResult` getting retained.

<img width="691" alt="image" src="https://user-images.githubusercontent.com/6490959/193704411-85979256-69bf-4db4-818e-f5d8d7888605.png">

We must find a way to not retain cluster states like this in the task results.
server/src/main/java/org/elasticsearch/action/admin/indices/rollover/TransportRolloverAction.java
/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the Elastic License
 * 2.0 and the Server Side Public License, v 1; you may not use this file except
 * in compliance with, at your election, the Elastic License 2.0 or the Server
 * Side Public License, v 1.
 */
package org.elasticsearch.action.admin.indices.rollover;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.admin.indices.stats.IndexStats;
import org.elasticsearch.action.admin.indices.stats.IndicesStatsAction;
import org.elasticsearch.action.admin.indices.stats.IndicesStatsRequest;
import org.elasticsearch.action.admin.indices.stats.IndicesStatsResponse;
import org.elasticsearch.action.admin.indices.stats.ShardStats;
import org.elasticsearch.action.support.ActionFilters;
import org.elasticsearch.action.support.ActiveShardsObserver;
import org.elasticsearch.action.support.IndicesOptions;
import org.elasticsearch.action.support.master.TransportMasterNodeAction;
import org.elasticsearch.client.internal.Client;
import org.elasticsearch.cluster.ClusterState;
import org.elasticsearch.cluster.ClusterStateTaskConfig;
import org.elasticsearch.cluster.ClusterStateTaskExecutor;
import org.elasticsearch.cluster.ClusterStateTaskListener;
import org.elasticsearch.cluster.block.ClusterBlockException;
import org.elasticsearch.cluster.block.ClusterBlockLevel;
import org.elasticsearch.cluster.metadata.IndexMetadata;
import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
import org.elasticsearch.cluster.metadata.Metadata;