fixed NPCList test in order not to break tests caching NPCList

src/games/stendhal/server/entity/npc/NPCList.java

@@ -47,7 +47,6 @@ public static NPCList get() {
 	}
 
 	protected NPCList() {
-		instance = this;
 		contents = new HashMap<String, SpeakerNPC>();
 
 	}

tests/games/stendhal/server/entity/npc/NPCListTest.java

@@ -15,25 +15,13 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertSame;
 
 import org.junit.Test;
 
-import games.stendhal.server.core.engine.SingletonRepository;
 import utilities.PlayerTestHelper;
 
 public class NPCListTest {
 
-	/**
-	 * Tests for get.
-	 */
-	@Test
-	public final void testGet() {
-		final NPCList npclist = new NPCList() {
-		};
-		assertSame(npclist, SingletonRepository.getNPCList());
-	}
-
 	/**
 	 * Tests for addHas.
 	 */