message: update_agent: adjust to new rand API
diff: @@ -132,7 +132,7 @@ impl UpdateAgent {
  use rand::Rng;
  let secs = period.as_secs();
  - let rand: u8 = rand::thread_rng().gen_range(0, 11);
  + let rand: u8 = rand::thread_rng().gen_range(0..=10);
  let jitter = u64::max(secs / 100, 1).saturating_mul(u64::from(rand));
  std::time::Duration::from_secs(secs.saturating_add(jitter))
  }
  