
**Bug description**
Unlike `cluster()`, `clusterAllReplicas()` does not implement `_shard_num`. 

I would expect
```
SELECT _shard_num
FROM clusterAllReplicas(prod, system.one)
ORDER BY _shard_num ASC
FORMAT PrettyCompactMonoBlock

┌─_shard_num─┐
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
│          0 │
└────────────┘
```
to have an output more useful like
```
SELECT _shard_num
FROM cluster(prod, system.one)
ORDER BY _shard_num ASC
FORMAT PrettyCompactMonoBlock

┌─_shard_num─┐
│          1 │
│          2 │
│          3 │
│          4 │
│          5 │
│          6 │
│          7 │
│          8 │
│          9 │
│         10 │
│         11 │
│         12 │
│         13 │
│         14 │
│         15 │
└────────────┘
```

**Releases where this has been tested**

* v20.3.12.112-stable

**References**

[cluster, clusterAllReplicas documentation](https://clickhouse.tech/docs/en/sql-reference/table-functions/cluster/)

[_shard_num documentation](https://clickhouse.tech/docs/en/engines/table-engines/special/distributed/#virtual-columns)

{
    if (is_prepared)
        throw Exception("MutationsInterpreter is already prepared. It is a bug.", ErrorCodes::LOGICAL_ERROR);
    if (commands.empty())
        throw Exception("Empty mutation commands list", ErrorCodes::LOGICAL_ERROR);
    const ColumnsDescription & columns_desc = metadata_snapshot->getColumns();
    const IndicesDescription & indices_desc = metadata_snapshot->getSecondaryIndices();
    NamesAndTypesList all_columns = columns_desc.getAllPhysical();
    NameSet updated_columns;
    for (const MutationCommand & command : commands)
    {
        for (const auto & kv : command.column_to_update_expression)
        {
            updated_columns.insert(kv.first);
        }
    }
    
    
    std::unordered_map<String, Names> column_to_affected_materialized;
    if (!updated_columns.empty())
    {
        for (const auto & column : columns_desc)