fix style issue

Author: yanghua

rust/lance/src/index/prefilter.rs

@@ -49,7 +49,7 @@ pub struct DatasetPreFilter {
     // and allow list at the same time we start searching the query.  We will await
     // these tasks only when we've done as much work as we can without them.
     pub(super) deleted_ids: Option<Arc<SharedPrerequisite<Arc<RowAddrMask>>>>,
-    pub(super) filtered_ids: Option<Arc<SharedPrerequisite<RowAddrMask>>> ,
+    pub(super) filtered_ids: Option<Arc<SharedPrerequisite<RowAddrMask>>>,
     // When the tasks are finished this is the combined filter
     pub(super) final_mask: Mutex<OnceCell<Arc<RowAddrMask>>>,
 }