Function render_sourcepos
pub fn render_sourcepos<T>(context: &mut Context<'_, '_, T>, node: Node<'_>) -> Result
Renders sourcepos data for the given node to the supplied Context.
This function renders anything iff context.options.render.sourcepos is
true, and includes a leading space if so, so you can use it unconditionally
immediately before writing a closing > in your opening HTML tag.