Constant rustc_hir_analysis::check::wfcheck::HELP_FOR_SELF_TYPE

const HELP_FOR_SELF_TYPE: &str = "consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, \
     `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one \
     of the previous types except `Self`)";