[fix] min and max window function bug fix

[cambyzju]

Proposed changes

Issue Number: close #8814

Problem Summary:

The difference between sql1 and sql2 is is_nullable, in sql1 TExprNode:is_nullable = true, but in sql2 TExprNode:is_nullable = false.

While is_nullable is false, min/max works not correctly. Because:

1. InitFn called by AggFnEvaluator::init, and _staging_intermediate_val is the return value;
2. At here _staging_intermediate_val->is_null == true and val = MAX for min aggregate;
3. next set_output_slot called, copy _staging_intermediate_val to destination Tuple;
4. becase _staging_intermediate_val is_null == true, set_output_slot do nothing, leave destination Tuple with default zero value;
5. Use zero value to calc min with positive number, always return zero.

Checklist(Required)

1. Does it affect the original behavior: (Yes/No/I Don't know)
2. Has unit tests been added: (Yes/No/No Need)
3. Has document been added or modified: (Yes/No/No Need)
4. Does it need to update dependencies: (Yes/No)
5. Are there any changes that cannot be rolled back: (Yes/No)

Further comments

If this is a relatively large or complex change, kick off the discussion at dev@doris.apache.org by explaining why you chose the solution you did and what alternatives you considered, etc...

[cambyzju]

This fix is not correctly, I close this pr temporarily and will update it later.

[HappenLee]

LGTM

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.