get_last_checkpoint does some unnecessary listing

[eeroel]

Environment

Delta-rs version: 0.10.2

---

Bug

Not a bug but a performance issue. When running update_incremental on an already-loaded table, get_last_checkpoint lists files starting from the last checkpoint, even if the loaded table is at a later version. This causes listing to take more time than necessary, as listing could start from self.version if it is larger than the last checkpoint version.
https://github.com/delta-io/delta-rs/blob/fdebcd67b59ca36e22b455065a7a32888122de0e/rust/src/delta.rs#L419C21-L419C21