**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))



if (alias_columns_required)
    {
        NameSet required_columns_from_prewhere; 
        NameSet required_aliases_from_prewhere; 
        if (prewhere_info)
        {
            
            auto prewhere_required_columns = prewhere_info->prewhere_actions->getRequiredColumns().getNames();
            required_columns_from_prewhere.insert(prewhere_required_columns.begin(), prewhere_required_columns.end());
            if (prewhere_info->row_level_filter)
            {
                auto row_level_required_columns = prewhere_info->row_level_filter->getRequiredColumns().getNames();
                required_columns_from_prewhere.insert(row_level_required_columns.begin(), row_level_required_columns.end());
            }
        }
        
        ASTPtr required_columns_all_expr = std::make_shared<ASTExpressionList>();
        
        ASTPtr required_columns_from_prewhere_expr = std::make_shared<ASTExpressionList>();
        
        
        for (const auto & column : required_columns)
        {
            ASTPtr column_expr;