update lastChase timestamp for mobs

src/engine/mobileAI/MobAI.java

@@ -901,6 +901,8 @@ public class MobAI {
             else if(System.currentTimeMillis() < mob.getTimestamps().get("lastChase").longValue() + 1000)
                     return;
 
+            mob.getTimestamps().put("lastChase",System.currentTimeMillis());
+
             if (CombatUtilities.inRange2D(mob, mob.getCombatTarget(), mob.getRange()) == false) {
                 if (mob.getRange() > 15) {
                     mob.destination = mob.getCombatTarget().getLoc();