[BUG] ROUND function returns FP result for FP value #1138
Description
What is the bug?
How can one reproduce the bug?
opensearchsql> select typeof(round(1.1)), round(1.1);
fetched rows / total rows = 1/1
+----------------------+--------------+
| typeof(round(1.1)) | round(1.1) |
|----------------------+--------------|
| DOUBLE | 1.0 |
+----------------------+--------------+
What is the expected behavior?
ROUND function should return an integer value (INTEGER or LONG).
It may happen that returned FP value is not an integer number (has digits after the point).