**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))



bool hasWindow() const { return !syntax->window_function_asts.empty(); }
    bool hasGlobalSubqueries() { return has_global_subqueries; }
    bool hasTableJoin() const { return syntax->ast_join; }
    const NamesAndTypesList & aggregationKeys() const { return aggregation_keys; }
    bool hasConstAggregationKeys() const { return has_const_aggregation_keys; }
    const AggregateDescriptions & aggregates() const { return aggregate_descriptions; }
    const PreparedSets & getPreparedSets() const { return prepared_sets; }
    std::unique_ptr<QueryPlan> getJoinedPlan();
    
    const TemporaryTablesMapping & getExternalTables() const { return external_tables; }
    ActionsDAGPtr simpleSelectActions();
    
    void appendSelect(ExpressionActionsChain & chain, bool only_types);
    
    ActionsDAGPtr appendProjectResult(ExpressionActionsChain & chain) const;
    
    void makeSetsForIndex(const ASTPtr & node);
private:
    StorageMetadataPtr metadata_snapshot;
    
    NameSet required_result_columns;
    SelectQueryOptions query_options;
    JoinPtr makeTableJoin(
        const ASTTablesInSelectQueryElement & join_element,
        const ColumnsWithTypeAndName & left_columns,
        ActionsDAGPtr & left_convert_actions);
    const ASTSelectQuery * getAggregatingQuery() const;
    /** These methods allow you to build a chain of transformations over a block, that receives values in the desired sections of the query.
      *
      * Example usage: