update changelog

CHANGELOG.md

@@ -39,6 +39,7 @@
     Bug #5415: Environment maps in ebony cuirass and HiRez Armors Indoril cuirass don't work
     Bug #5416: Junk non-node records before the root node are not handled gracefully
     Bug #5422: The player loses all spells when resurrected
+    Bug #5423: Guar follows actors too closely
     Bug #5424: Creatures do not headtrack player
     Bug #5425: Poison effect only appears for one frame
     Bug #5427: GetDistance unknown ID error is misleading