executor: fix test problems in TestIssue20658 (#21442)
executor: fix test problems in TestIssue20658 (#21442)

 
pingcap/tidb,kyle-wang/tidb,pingcap/tidb,kyle-wang/tidb,ngaut/tidb,coocood/tidb,coocood/tidb,c4pt0r/tidb,kyle-wang/tidb,c4pt0r/tidb,ngaut/tidb,c4pt0r/tidb,c4pt0r/tidb,pingcap/tidb,kyle-wang/tidb,kyle-wang/tidb,pingcap/tidb,kyle-wang/tidb,c4pt0r/tidb,c4pt0r/tidb,ngaut/tidb,ngaut/tidb,ngaut/tidb,pingcap/tidb,ngaut/tidb,pingcap/tidb