**Describe what's wrong**

Query with rollup using same selected field name as the name of underlying column reports structure mismatch

**Does it reproduce on recent release?**

yes

**How to reproduce**

`21.9.2.17`

```sql
CREATE TABLE test
(
    `d` DateTime,
    `a` LowCardinality(String),
    `b` UInt64
)
ENGINE = MergeTree
PARTITION BY toDate(d)
ORDER BY d;

SELECT *
FROM (
    SELECT
        a,
        max((d, b)).2 AS value
    FROM test
    GROUP BY rollup(a)
)
WHERE a <> '';
```

**Expected behavior**

This used to return an ok result on v21.8

**Error message and/or stacktrace**

> Code: 352. DB::Exception: Block structure mismatch in (columns with identical name must have identical structure) stream: different columns:
> notEquals(a, '') LowCardinality(UInt8) ColumnLowCardinality(size = 0, UInt8(size = 0), ColumnUnique(size = 1, UInt8(size = 1)))
> notEquals(a, '') LowCardinality(UInt8) Const(size = 0, ColumnLowCardinality(size = 1, UInt8(size = 1), ColumnUnique(size = 2, UInt8(size = 2)))). (AMBIGUOUS_COLUMN_NAME) (version 21.9.2.17 (official build))



NameSet columns_to_remove(columns_to_remove_after_prewhere.begin(), columns_to_remove_after_prewhere.end());
            Block prewhere_actions_result = prewhere_info->prewhere_actions->getResultColumns();
            
            
            for (const auto & column : prewhere_actions_result)
            {
                if (prewhere_info->remove_prewhere_column && column.name == prewhere_info->prewhere_column_name)
                    continue;
                if (columns_to_remove.count(column.name))
                    continue;
                required_columns_all_expr->children.emplace_back(std::make_shared<ASTIdentifier>(column.name));
                required_columns_after_prewhere.emplace_back(column.name, column.type);
            }
            required_columns_after_prewhere_set
                = collections::map<NameSet>(required_columns_after_prewhere, [](const auto & it) { return it.name; });
        }
        auto syntax_result
            = TreeRewriter(context).analyze(required_columns_all_expr, required_columns_after_prewhere, storage, metadata_snapshot);
        alias_actions = ExpressionAnalyzer(required_columns_all_expr, syntax_result, context).getActionsDAG(true);
        
        required_columns = alias_actions->getRequiredColumns().getNames();
        
        if (prewhere_info && prewhere_info->remove_prewhere_column)
            if (required_columns.end() != std::find(required_columns.begin(), required_columns.end(), prewhere_info->prewhere_column_name))
                prewhere_info->remove_prewhere_column = false;
        
        std::erase_if(required_columns, [&](const String & name) { return required_columns_after_prewhere_set.count(name) != 0; });
        if (prewhere_info)
        {