Fix after upgrade of crossterm

Summary:
[Bugreport](https://fb.workplace.com/groups/buck2users/posts/3477532612503095). Caused by crossterm upgrade D48118707.

Crossterm version 0.24.0 includes [strange change](crossterm-rs/crossterm@0a435e6#diff-d652bc172cf95622c9c34f43bd6ed9a6c27f042945f710cb9025cae7b12dd579L179-L185):

They say: "Most terminals default 0 argument to 1". OK. Then why revert cross-terminal behavior to terminal-specific?

This diff applies reverses this this crossterm change in superconsole.

Reviewed By: ndmitchell, JakobDegen

Differential Revision: D48165006

fbshipit-source-id: 3569c5947809f1908c35415922ef9640750bfdff

src/components/canvas.rs

@@ -63,7 +63,9 @@ impl Canvas {
     /// This is used to clear the scratch area so that any possibly emitted messages can write over it.
     pub(crate) fn move_up(&self, writer: &mut Vec<u8>) -> anyhow::Result<()> {
         let len = self.last_lines.take();
-        writer.queue(MoveUp(len))?;
+        if len != 0 {
+            writer.queue(MoveUp(len))?;
+        }
         writer.queue(MoveToColumn(0))?;
 
         Ok(())