### Elasticsearch Version

All

### Installed Plugins

N/A

### Java Version

_bundled_

### OS Version

N/A

### Problem Description

Today if an index has an `index.auto_expand_replicas` setting which cannot be realised in the cluster then the number of replicas is left unchanged by `AllocationService#adaptAutoExpandReplicas()`. Instead, I think we should change the number of replicas to the closest value within the permitted range.

For instance: if a cluster has a single data node which is marked as shutting down for restart then auto-expand replicas considers this cluster to have zero data nodes, and hence requires -1 replicas. If an index is created with `index.auto_expand_replicas: "0-1"` then it will not be adjusted to have zero replicas, even though this would be better than leaving it at the default value of 1 replica, and will ultimately be the correct setting.

### Steps to Reproduce

1. Create a cluster with one data node.
2. Put a `RESTART` shutdown marker on the data node.
3. Create an index with `index.auto_expand_replicas: "0-1"`
4. Observe that this results in an unassigned replica.

### Logs (if relevant)

_No response_
server/src/test/java/org/elasticsearch/cluster/metadata/AutoExpandReplicasTests.java
final ThreadPool threadPool = new TestThreadPool(getClass().getName());
        final ClusterStateChanges cluster = new ClusterStateChanges(xContentRegistry(), threadPool);
        try {
            List<DiscoveryNode> allNodes = new ArrayList<>();
            DiscoveryNode localNode = createNode(
                VersionUtils.randomVersionBetween(random(), Version.V_7_0_0, Version.V_7_5_1),
                DiscoveryNodeRole.MASTER_ROLE,
                DiscoveryNodeRole.DATA_ROLE
            ); 
            DiscoveryNode oldNode = createNode(
                VersionUtils.randomVersionBetween(random(), Version.V_7_0_0, Version.V_7_5_1),
                DiscoveryNodeRole.DATA_ROLE
            ); 
            allNodes.add(localNode);
            allNodes.add(oldNode);
            ClusterState state = ClusterStateCreationUtils.state(localNode, localNode, allNodes.toArray(new DiscoveryNode[0]));
            CreateIndexRequest request = new CreateIndexRequest(
                "index",
                Settings.builder().put(SETTING_NUMBER_OF_SHARDS, 1).put(SETTING_AUTO_EXPAND_REPLICAS, "0-all").build()
            ).waitForActiveShards(ActiveShardCount.NONE);
            state = cluster.createIndex(state, request);
            assertTrue(state.metadata().hasIndex("index"));
            while (state.routingTable().index("index").shard(0).allShardsStarted() == false) {
                logger.info(state);
                state = cluster.applyStartedShards(
                    state,
                    state.routingTable().index("index").shard(0).shardsWithState(ShardRoutingState.INITIALIZING)
                );
                state = cluster.reroute(state, new ClusterRerouteRequest());
            }