SPIGOT-5142: Ignore invalid firework effects

src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaFirework.java

@@ -90,7 +90,11 @@ class CraftMetaFirework extends CraftMetaItem implements FireworkMeta {
         List<FireworkEffect> effects = this.effects = new ArrayList<FireworkEffect>(fireworkEffects.size());
 
         for (int i = 0; i < fireworkEffects.size(); i++) {
+            try {
                 effects.add(getEffect((NBTTagCompound) fireworkEffects.get(i)));
+            } catch (IllegalArgumentException ex) {
+                // Ignore invalid effects
+            }
         }
     }