[css-navigation-1][editorial] Remove extra punctuation.

Author: dbaron

css-navigation-1/Overview.bs

@@ -489,8 +489,8 @@ and the pseudo-class matches any element where:
                             navigation-from | navigation-to
 </pre>
 
-ISSUE: Should we use ''navigation-''-(''at''/''with''/''from''/''to'') or
-''navigation-''/(''current''/''other''/''from''/''to'')?
+ISSUE: Should we use ''navigation-''(''at''/''with''/''from''/''to'') or
+''navigation-''(''current''/''other''/''from''/''to'')?
 
 ISSUE: Should the '':link-to()'' variant that has a <<link-condition>> have a different name,
 such as '':navigating-link()''?