message: Do not publish if namespace = "_"
diff: @@ -151,7 +151,16 @@ impl Publish {
  .namespace,
  )
  })
  - .unwrap_or_else(|| "_".to_string());
  + .ok_or_else(|| {
  + anyhow::anyhow!(
  + "no namespace found in package name {:?}",
  + manifest.package.name
  + )
  + })?;
  +
  + if namespace == "_" {
  + return Err(anyhow::anyhow!("cannot publish with namespace = \"_\""));
  + }
  if !wasmer_registry::utils::user_can_publish_under_namespace(
  &registry, &username, &namespace,
  