Tiny supportability nit: today we emit these log messages when adding a write block to an index:

```
[2022-03-22T19:43:26,897][INFO ][o.e.c.m.MetadataIndexStateService] [node_t1] adding block write to indices [[test-blocks/eLkrYpm_S3WNemfWpXrhPA]]
[2022-03-22T19:43:26,933][INFO ][o.e.c.m.MetadataIndexStateService] [node_t1] completed adding block write to indices [test-blocks]
```

This is kind of confusing, a `block write` sounds like we're writing a block of data. It's not clear that `write` is variable (we also say `block read`) or the name of a block setting. I think we should word this as `adding [index.blocks.write] block to indices` instead.
server/src/main/java/org/elasticsearch/cluster/metadata/MetadataIndexStateService.java
"index.verified_before_close",
        false,
        Setting.Property.IndexScope,
        Setting.Property.PrivateIndex
    );
    private final ClusterService clusterService;
    private final AllocationService allocationService;
    private final IndexMetadataVerifier indexMetadataVerifier;
    private final IndicesService indicesService;
    private final ShardLimitValidator shardLimitValidator;
    private final NodeClient client;
    private final ThreadPool threadPool;
    private final ActiveShardsObserver activeShardsObserver;
    private final ClusterStateTaskExecutor<OpenIndicesTask> opensExecutor;
    private final ClusterStateTaskExecutor<AddBlocksToCloseTask> addBlocksToCloseExecutor;
    private final ClusterStateTaskExecutor<CloseIndicesTask> closesExecutor;
    private final ClusterStateTaskExecutor<AddBlocksTask> addBlocksExecutor;
    private final ClusterStateTaskExecutor<FinalizeBlocksTask> finalizeBlocksExecutor;
    @Inject
    public MetadataIndexStateService(
        ClusterService clusterService,
        AllocationService allocationService,
        IndexMetadataVerifier indexMetadataVerifier,
        IndicesService indicesService,
        ShardLimitValidator shardLimitValidator,
        NodeClient client,
        ThreadPool threadPool
    ) {
        this.clusterService = clusterService;
        this.allocationService = allocationService;