message: print should output a newline
diff: @@ -247,7 +247,9 @@ pub fn execute<T: std::io::Write>(
  Print { args } => {
  write!(
  out,
  - "{}",
  + // NOTE: The Bril spec implies print should just output its arguments, with no newline.
  + // However, brili uses console.log, which does add a newline, so we will too
  + "{}\n",
  args
  .iter()
  .map(|a| format!("{}", store[a.0]))
  