Fix typo in Representing Time section.

Author: msporny

index.html

@@ -3780,7 +3780,7 @@ <h3>Representing Time</h3>
           <li>
 Leap seconds might not be taken into account in all software systems, especially
 for dates and times that precede the introduction of the leap second. Leap
-seconds can affects highly sensitive systems that depend on the exact
+seconds can affect highly sensitive systems that depend on the exact
 millisecond offset from the epoch. However, note that for most applications the
 only moment in time that is affected is the one second period of the leap second
 itself. That is, the moment after the most recent leap second can always be