message: log crate & version for failing yanks/unyanks
diff: @@ -284,7 +284,10 @@ fn set_yanked(conn: &mut postgres::Client, name: &str, version: &str, yanked: bo
  {
  Ok(rows) => {
  if rows != 1 {
  - error!("tried to yank or unyank non-existing release");
  + error!(
  + "tried to yank or unyank non-existing release: {} {}",
  + name, version
  + );
  } else {
  debug!("{}-{} {}", name, version, activity);
  }
  