fix(tvix/cli): Make :q actually quit

whoops

Change-Id: I5f24163c276992c7858b038ae2bb636da75f3f91
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12043
Autosubmit: aspen <root@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: lukegb <lukegb@tvl.fyi>

tvix/cli/src/repl.rs

@@ -178,7 +178,7 @@ impl<'a> Repl<'a> {
             ReplCommand::Quit => {
                 return CommandResult {
                     output: String::new(),
-                    continue_: true,
+                    continue_: false,
                 };
             }
             ReplCommand::Help => {