Column count doesn't match value count when executing insert SQL using prepare + execute

[Damon-Guo]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

create table t1 (a int(11) ,b varchar(100) ,primary key (a));
create table t2 (c int(11) ,d varchar(100) ,primary key (c));
prepare in1 from "insert into t1 (a,b) select c,null from t2 t on duplicate key update b=t.d" ;
execute in1 ;

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

v5.3.2
v6.1.0

[Reminiscent]

related to #14412