[css-logical-1] Add link to some issues.

Author: fantasai

css-logical-1/Overview.bs

@@ -354,6 +354,10 @@ Flow-Relative Box Model Properties</h2>
   (such as <code>getComputedStyle()</code>)
   must return the same value for equivalent pairs of such properties.
 
+  ISSUE: There are some open questions on
+  the <a href="https://github.com/w3c/csswg-drafts/issues/3029">order of inheritance vs mapping in flow-relative properties</a>
+  and on the <a href="https://github.com/w3c/csswg-drafts/issues/3030">interaction of shorthands and logical properties</a>.
+
 <h3 id="dimension-properties">
 Logical Height and Logical Width: the 'block-size' and 'inline-size' properties</h3>