**How to reproduce**
Clickhouse version 21.2-21.3

```
SELECT x
FROM
(
    SELECT 1 AS x
    UNION DISTINCT
    SELECT 1
)
LIMIT 1

Query id: b82bbb8d-dea9-4f1c-9a2f-5b0e9b6c2422


0 rows in set. Elapsed: 0.002 sec.

Received exception from server (version 21.2.3):
Code: 49. DB::Exception: Received from localhost:9000. DB::Exception: Bad cast from type DB::ASTSelectWithUnionQuery to DB::ASTSelectQuery.
```


{
    UInt64 length = 0;
    UInt64 offset = 0;
    if (query.limitLength())
    {
        length = getLimitUIntValue(query.limitLength(), context, "LIMIT");
        if (query.limitOffset() && length)
            offset = getLimitUIntValue(query.limitOffset(), context, "OFFSET");
    }
    else if (query.limitOffset())
        offset = getLimitUIntValue(query.limitOffset(), context, "OFFSET");
    return {length, offset};
}
static UInt64 getLimitForSorting(const ASTSelectQuery & query, const Context & context)
{
    
    if (!query.distinct && !query.limitBy() && !query.limit_with_ties && !query.arrayJoinExpressionList() && query.limitLength())
    {
        auto [limit_length, limit_offset] = getLimitLengthAndOffset(query, context);
        if (limit_length > std::numeric_limits<UInt64>::max() - limit_offset)
            return 0;
        return limit_length + limit_offset;
    }
    return 0;
}
static bool hasWithTotalsInAnySubqueryInFromClause(const ASTSelectQuery & query)