Introduce new progress steps when deleting fid-based entries

crates/milli/src/update/new/steps.rs

@@ -28,6 +28,8 @@ make_enum_progress! {
         ChangingVectorStore,
         UsingStableIndexer,
         UsingExperimentalIndexer,
+        DeletingOldWordFidDocids,
+        DeletingOldFidWordCountDocids,
     }
 }