fix: fix incorrect COM_STMT_PREPARE reply

[WenyXu]

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fix #3462

What's changed and what's your intention?

fix incorrect COM_STMT_PREPARE reply.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

[killme2008]

LGTM. But could we add a test case to cover it?

[waynexia]

But could we add a test case to cover it?

Maybe add one integration test with sqlx?

[WenyXu]

LGTM. But could we add a test case to cover it?

Yes, we can cover this case by using row.get("col_name");;

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.07%. Comparing base (3f3ef2e) to head (6f245e5).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3463      +/-   ##
==========================================
- Coverage   85.41%   85.07%   -0.34%     
==========================================
  Files         896      896              
  Lines      147185   147532     +347     
==========================================
- Hits       125711   125507     -204     
- Misses      21474    22025     +551