HttT 14: remove loyal overlay over spider

There's no reason why a monster should have an overlay.

[ci skip]

data/campaigns/Heir_To_The_Throne/scenarios/14_Plunging_Into_the_Darkness.cfg

@@ -66,6 +66,8 @@
         side=2
         no_leader=yes
         hidden=yes
+        team_name=monsters
+        user_team_name=_"Monsters"
         [ai]
             {ATTACK_DEPTH 4 5 5}
             aggression=1.0
@@ -100,7 +102,13 @@
             ai_special=guardian
         [/unit]
 
-        {NAMED_LOYAL_UNIT 2 (Giant Spider) 16 40 (Hywyn) ( _ "Hywyn")}
+        [unit]
+            name= _ "Hywyn"
+            type=Giant Spider
+            x=16
+            y=40
+            side=2
+        [/unit]
     [/side]
 
     [side]