Incorrect result from DISTINCT clause in Gen4

[GuptaManan100]

Overview of the Issue

The following query generates incorrect results -

SELECT DISTINCT order2s.`status` FROM order2s

The result for this query is -

+--------+
| status |
+--------+
|      3 |
|      2 |
|      0 |
|      1 |
|      2 |
|      0 |
|      1 |
|      3 |
+--------+

The problem has been traced back to Gen4 planning. The V3 plan is as follows

{
  "QueryType": "SELECT",
  "Original": "select distinct user.`intcol` from user",
  "Instructions": {
    "OperatorType": "Aggregate",
    "Variant": "Ordered",
    "GroupBy": "0",
    "Inputs": [
      {
        "OperatorType": "Route",
        "Variant": "SelectScatter",
        "Keyspace": {
          "Name": "user",
          "Sharded": true
        },
        "FieldQuery": "select `user`.intcol from `user` where 1 != 1",
        "OrderBy": "0 ASC",
        "Query": "select distinct `user`.intcol from `user` order by intcol asc",
        "Table": "`user`"
      }
    ]
  }
}

The difference between V3 and Gen4 is as follows

- 	        "OrderBy": "0 ASC",
- 	        "Query": "select distinct `user`.intcol from `user` order by intcol asc",
+ 	        "Query": "select distinct `user`.intcol from `user`",

Reproduction Steps

Steps to reproduce this issue, example:

1. Add the query to onecase.txt
2. Run the test TestOneCase

Binary version

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