message: Add delayed warning to manifest. Pass test
diff: @@ -1021,6 +1021,8 @@ impl TomlManifest {
  None => false,
  };
  + let warn_default_feat = summary.features().contains_key("default-features");
  +
  let custom_metadata = project.metadata.clone();
  let mut manifest = Manifest::new(
  summary,
  @@ -1056,6 +1058,12 @@ impl TomlManifest {
  for error in errors {
  manifest.warnings_mut().add_critical_warning(error);
  }
  + if warn_default_feat {
  + manifest.warnings_mut().add_warning(
  + "`default-features = [\"..\"]` was found in [features]. \
  + Did you mean to use `default = [\"..\"]`?".to_string()
  + );
  + }
  manifest.feature_gate()?;
  