adding example values for help urls to .env.examples - missed commit for https://trello.com/c/TBWqpIA8/677-link-to-digital-guidelines-from-site-editor
adding example values for help urls to .env.examples - missed commit for https://trello.com/c/TBWqpIA8/677-link-to-digital-guidelines-from-site-editor

unikent/astro,unikent/astro,unikent/astro,unikent/astro,unikent/astro