fix extra , at the end of the changelog line

debian/changelog

@@ -121,7 +121,7 @@ apt (0.7.22) unstable; urgency=low
   [ Osamu Aoki ]
   * Updated cron script to support backups by hardlinks and 
     verbose levels.  All features turned off by default. 
-  * Added more error handlings.  Closes: #438803, #462734, #454989, 
+  * Added more error handlings.  Closes: #438803, #462734, #454989
   * Documented all cron script related configuration items in 
     configure-index.