[css-nav-1] Remove the closed issue

Author: Jihye Hong

css-nav-1/Overview.bs

@@ -1050,8 +1050,6 @@ and unset when the focus is moved (by spatial navigation or any other means).
 If the UA sets both a <a>spatial navigation starting point</a> and a <a>sequential focus navigation starting point</a>,
 they must not be set differently.
 
-Issue(23): The focusing steps should probably reset the <a>spatial navigation starting point</a>
-
 <div algorithm="to run the spatial navigation steps">
 To run the <dfn>spatial navigation steps</dfn> in <var>direction</var>, do the following: