Can now open secret walls and pick up machine gun

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

lib/features/weapon/weapons/knife.dart

@@ -8,6 +8,7 @@ class Knife extends Weapon {
         fireFrames: [417, 418, 419, 420],
         damage: 15,
         msPerFrame: 120,
+        isAutomatic: false,
       );
 
   @override