**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))



{
    auto & query = getSelectQuery();
    if (query.orderBy())
    {
        SortDescription order_descr = getSortDescription(query, context);
        SortDescription fill_descr;
        for (auto & desc : order_descr)
        {
            if (desc.with_fill)
                fill_descr.push_back(desc);
        }
        if (fill_descr.empty())
            return;
        auto filling_step = std::make_unique<FillingStep>(query_plan.getCurrentDataStream(), std::move(fill_descr));
        query_plan.addStep(std::move(filling_step));
    }
}
void InterpreterSelectQuery::executeLimit(QueryPlan & query_plan)