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
continue;
                }
                final IndexMetadata indexMetadata = metadata.getSafe(index);
                if (indexMetadata.getState() == IndexMetadata.State.CLOSE) {
                    logger.debug("verification of shards before closing {} succeeded but index is already closed", index);
                    assert currentState.blocks().hasIndexBlock(index.getName(), INDEX_CLOSED_BLOCK);
                    continue;
                }
                final ClusterBlock closingBlock = blockedIndices.get(index);
                assert closingBlock != null;
                if (currentState.blocks().hasIndexBlock(index.getName(), closingBlock) == false) {
                    
                    closingResults.put(
                        result.getKey(),
                        new IndexResult(
                            result.getKey(),
                            new IllegalStateException(
                                "verification of shards before closing " + index + " succeeded but block has been removed in the meantime"
                            )
                        )
                    );
                    logger.debug("verification of shards before closing {} succeeded but block has been removed in the meantime", index);
                    continue;
                }
                
                Set<Index> restoringIndices = RestoreService.restoringIndices(currentState, Set.of(index));
                if (restoringIndices.isEmpty() == false) {
                    closingResults.put(
                        result.getKey(),
                        new IndexResult(