[css-logical] Fix typo, switch issue to note since it's resolved.

Author: fantasai

css-logical/Overview.bs

@@ -221,11 +221,11 @@ Flow-Relative Box Model Properties</h2>
   depends on the element’s computed values of
   'writing-mode', 'direction', and 'text-orientation'.
 
-  Issue: Depending on the element’s own writing mode
+  Note: Depending on the element’s own writing mode
   simplifies the cascading calculations
   and gives a straightforward model for authors to reason about.
   However, it is problematic in many cases,
-  see for example <a href="https://www.w3.org/mid/20161108202634.GA7235@mail.internode.on.net">this discussiona</a>.
+  see for example <a href="https://www.w3.org/mid/20161108202634.GA7235@mail.internode.on.net">this discussion</a>.
 
   A computed value that has flow-relative and physical properties as input
   is determined by applying the CSS cascade to declarations of both.