MVCC Scanner unit tests: Add test for scanner under lock (#5474)
MVCC Scanner unit tests: Add test for scanner under lock (#5474)

Signed-off-by: mapleFU <c2be1dc05d3d43706785f783669dd34b945aab9a@qq.com>
BusyJay/tikv,BusyJay/tikv,pingcap/tikv,pingcap/tikv,c4pt0r/tikv,BusyJay/tikv,BusyJay/tikv