[Bug] Plan with parameterized path may always be wrong

### Cloudberry Database version

All versions affected

Also GP7 have the same issue.

### What happened

```
create table t1(v varchar(100));
insert into t1 values('abc~001');

create or replace function sameout
(in vc varchar) returns varchar AS $BODY$
begin
return vc;
END;
$BODY$
LANGUAGE plpgsql;

set optimizer to off;
select (select sameout(v) t) from t1; -- will coredump
```

This case has nothing to do with the table itself and the custom function. Only relative the parameterized path.

**ORCA also will got the same issue with other sql.**

So the SQL `select (select sameout(v) t) from t1; ` plan is

```
QUERY PLAN
---------------------------------------------------------------------------------------
Gather Motion 1:1 (slice1; segments: 1) (cost=0.00..3928.00 rows=13200 width=32)
Output: ((SubPlan 1))
-> Seq Scan on public.t1 (cost=0.00..3664.00 rows=13200 width=32)
Output: (SubPlan 1)
SubPlan 1
-> Materialize (cost=0.00..0.00 rows=0 width=0)
Output: (sameout(t1.v))
-> Broadcast Motion 1:1 (slice2) (cost=0.00..0.26 rows=1 width=32)
Output: (sameout(t1.v))
-> Result (cost=0.00..0.26 rows=1 width=32)
Output: sameout(t1.v)
Optimizer: Postgres query optimizer
(12 rows)
```

As u can see we do have a `Motion` node exist in subplan. Then in `Result` node won't get any tuple in this path.

I guess this case is caused by optimizer. The optimizer should not create the parameterized path with the motion.

### What you think should happen instead

this sql can change to the `select sameout(v) from t1; ` or a subquery `select sameout(v) from (select v from t1) t;`

The corrent plan should flat the parameterized path or become a subquery
```
QUERY PLAN
---------------------------------------------------------------------------------------
Gather Motion 1:1 (slice1; segments: 1) (cost=0.00..3928.00 rows=13200 width=32)
-> Output: (sameout(t1.v))
-> Broadcast Motion 1:1 (slice2) (cost=0.00..0.26 rows=1 width=32)
Output: (sameout(t1.v))
-> Seq Scan on public.t1 (cost=0.00..3664.00 rows=13200 width=32)

Optimizer: Postgres query optimizer
(12 rows)

```

or no motion inside

```
QUERY PLAN
----------------------------------------------------------------------------------------------------------------
Result (cost=0.00..882732.09 rows=1 width=8)
Output: (SubPlan 1)
-> Gather Motion 1:1 (slice1; segments: 1) (cost=0.00..431.00 rows=1 width=8)
Output: v
-> Seq Scan on public.t1 (cost=0.00..431.00 rows=1 width=8)
Output: v
SubPlan 1
-> Materialize (cost=0.00..0.00 rows=0 width=0)
Output: (sameout(t1.v))
-> Result (cost=0.00..0.26 rows=1 width=32)
Output: sameout(t1.v)
(20 rows)
```

### How to reproduce

above

### Operating System

any

### Anything else

_No response_

### Are you willing to submit PR?

- [ ] Yes, I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://cloudberrydb.org/community/coc).

Start by running the supplied SQL reproduction with the optimizer disabled and inspect the generated plan around the parameterized path, Motion, Result, and SubPlan nodes. Compare the observed plan with the two expected alternatives; done means the query no longer coredumps and the optimizer avoids an invalid Motion inside the parameterized path.

Written by the indexing model from the issue text.