#640: Add new Causes for LightningStrikeEvent

By: Doc <nachito94@msn.com>

paper-api/src/main/java/org/bukkit/event/weather/LightningStrikeEvent.java

@@ -72,6 +72,14 @@ public class LightningStrikeEvent extends WeatherEvent implements Cancellable {
          * Triggered by the /summon command.
          */
         COMMAND,
+        /**
+         * Triggered by a Plugin.
+         */
+        CUSTOM,
+        /**
+         * Triggered by a Spawner.
+         */
+        SPAWNER,
         /**
          * Triggered by an enchanted trident.
          */