message: Remove the &T instance for AsMarkdown
  Summary: I think auto-deref will mean this is never necessary.
diff: @@ -60,16 +60,12 @@ impl AsMarkdown for String {
  Some(self.clone())
  }
  }
  +
  impl AsMarkdown for str {
  fn generate_markdown(&self, _flavor: MarkdownFlavor) -> Option<String> {
  Some(self.to_owned())
  }
  }
  -impl<T: AsMarkdown> AsMarkdown for &T {
  - fn generate_markdown(&self, flavor: MarkdownFlavor) -> Option<String> {
  - (*self).generate_markdown(flavor)
  - }
  -}
  /// What to render from a [`DocString`].
  enum DSOpts {
  