Missing SQL set operations in SetOperation class

Missing SQL set operations in SetOperation class: a task in harbor-swesmith-rl-artifacts: Harbor SWE-Smith 强化学习数据产物 (Harbor dataset). Describe the bug After a recent update, several SQL set operations are no longer working. Specifically, the intersect and minus operations are failing when trying…

The task

**Describe the bug** After a recent update, several SQL set operations are no longer working. Specifically, the `intersect` and `minus` operations are failing when trying to use them in queries.

Part of keryszhan/harbor-swesmith-rl-artifacts.