message: Fix subdomain error message formatting
diff: @@ -110,11 +110,11 @@ pub fn set_subdomain(name: &str, user: &GlobalUser, target: &Target) -> Result<(
  if let Some(subdomain) = subdomain {
  let msg;
  if subdomain == name {
  - msg = "{} You have previously registered {}.workers.dev";
  + msg = format!("You have previously registered {}.workers.dev", subdomain);
  } else {
  - msg = "{} This account already has a registered subdomain. You can only register one subdomain per account. Your subdomain is {}.workers.dev";
  + msg = format!("This account already has a registered subdomain. You can only register one subdomain per account. Your subdomain is {}.workers.dev", subdomain);
  }
  - failure::bail!(format!(msg, emoji::WARN, subdomain))
  + failure::bail!(msg)
  } else {
  register_subdomain(&name, &user, &target)
  }
  