adjust MakeNormalDelete.deleteLine implementation slightly, because the previous implementation did not delete the last character when we are at the end of the file

fcore/normal-mode/make-normal-delete.sml

@@ -275,10 +275,10 @@ struct
     let
       val {buffer, cursorIdx, searchString, ...} = app
       val buffer = LineGap.goToIdx (cursorIdx, buffer)
+      val textLength = #textLength buffer
 
       val startIdx = Cursor.vi0 (buffer, cursorIdx)
-      val finishIdx = Cursor.viDlrForDelete (buffer, cursorIdx, count)
+      val finishIdx = Cursor.viDlr (buffer, cursorIdx, count) + 2
-
       val length = finishIdx - startIdx
     in
       deleteAndFinish (app, startIdx, length, buffer, time)