Link to full Medium URL on error page

Previously the link on the error page was only linking to the path
component of the url, e.g. `/search` but ignoring any query params e.g.
`/search?q=hello`. This uses the HTTP::Request `resource` method which
appears to capture both.

src/actions/articles/show.cr

@@ -12,8 +12,8 @@ class Articles::Show < BrowserAction
       html(
         Errors::ParseErrorPage,
         message: "Error parsing the URL",
-        status_code: 500,
-        original_path: request.path,
+        status_code: 422,
+        original_resource: request.resource,
       )
     end
   end

src/pages/errors/parse_error_page.cr

@@ -1,7 +1,7 @@
 class Errors::ParseErrorPage < MainLayout
   needs message : String
   needs status_code : Int32
-  needs original_path : String
+  needs original_resource : String
 
   def page_title
     "Error"
@@ -25,7 +25,7 @@ class Errors::ParseErrorPage < MainLayout
       TEXT
       para do
         text "If you like, you can try visiting "
-        a "this page on medium.com", href: "https://medium.com#{original_path}"
+        a "this page on medium.com", href: "https://medium.com#{original_resource}"
       end
     end
   end