Revert "Merge pull request #4568 from deathbeam/proper-shutdown"

This reverts commit 8d53997685, reversing
changes made to 4f548e835c.

This is crashing on shutdown.

runescape-api/src/main/java/net/runelite/rs/api/RSGameEngine.java

@@ -32,7 +32,4 @@ public interface RSGameEngine extends GameEngine
 {
 	@Import("canvas")
 	Canvas getCanvas();
-
-	@Import("shutDown")
-	void shutDown();
 }