when I try to make an update `{ $set: { "a.b.1.2": 1 } }`, the actually executed update was `{ $set: { "a.b.1": 1 } }`. https://github.com/hu-chia/minimal-reproduce-to-mongo-update-be-broken/blob/64fa3dc694c0db3b1813d3718194bd5be4e4ccd6/src/test/java/com/example/mongoupdate/TestMongoUpdateApplication.java#L30 ### minimal reproduce https://github.com/hu-chia/minimal-reproduce-to-mongo-update-be-broken.git