let plan replayer sql return proper information even when it meets error

## Enhancement
For now, if the plan replayer meets an error, it would return an error. For example:
```sql
create table t(a int primary key, b int);
insert into t select 1,1;
plan replayer dump explain analyze insert into t select 1,1;
```
```
ERROR 1062 (23000): Duplicate entry '1' for key 't.PRIMARY'
```
The better behavior is to always return the plan replayer dump file, and record the error properly in that.