…otation

### What changes were proposed in this pull request?

This PR marks overridden methods with `Override` annotation.

### Why are the changes needed?

An overridden method from an interface or abstract class must be marked with `Override` annotation. To accurately determine whether the overriding is successful, an `Override` annotation is necessary. Meanwhile, once the method signature in the abstract class is changed, the implementation class will report a compile-time error immediately.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Pass the unit test.

Closes #36461 from dcoliversun/SPARK-39111.

Authored-by: Qian.Sun <qian.sun2020@gmail.com>
Signed-off-by: Sean Owen <srowen@gmail.com>