**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))



const ASTTablesInSelectQueryElement & join_element,
    const ColumnsWithTypeAndName & left_columns,
    ActionsDAGPtr & left_convert_actions)
{
    
    if (joined_plan)
        throw Exception(ErrorCodes::LOGICAL_ERROR, "Table join was already created for query");
    ActionsDAGPtr right_convert_actions = nullptr;
    const auto & analyzed_join = syntax->analyzed_join;
    if (auto storage = analyzed_join->getStorageJoin())
    {
        std::tie(left_convert_actions, right_convert_actions) = analyzed_join->createConvertingActions(left_columns, {});
        return storage->getJoinLocked(analyzed_join);
    }
    joined_plan = buildJoinedPlan(getContext(), join_element, *analyzed_join, query_options);
    const ColumnsWithTypeAndName & right_columns = joined_plan->getCurrentDataStream().header.getColumnsWithTypeAndName();
    std::tie(left_convert_actions, right_convert_actions) = analyzed_join->createConvertingActions(left_columns, right_columns);
    if (right_convert_actions)
    {
        auto converting_step = std::make_unique<ExpressionStep>(joined_plan->getCurrentDataStream(), right_convert_actions);
        converting_step->setStepDescription("Convert joined columns");
        joined_plan->addStep(std::move(converting_step));
    }
    JoinPtr join = chooseJoinAlgorithm(analyzed_join, joined_plan->getCurrentDataStream().header, getContext());
    
    if (analyzed_join->getDictionaryReader())
        joined_plan.reset();
    return join;
}
ActionsDAGPtr SelectQueryExpressionAnalyzer::appendPrewhere(