Try fix gamemode test

Author: benwoo1110

src/test/java/org/mvplugins/multiverse/inventories/handleshare/GameModeChangeTest.kt

@@ -52,6 +52,8 @@ class GameModeChangeTest : TestWithMockBukkit() {
         assertNotEquals(creativeItems[0], player.inventory.getItem(0))
         assertNotEquals(creativeItems[1], player.inventory.getItem(1))
 
+        Thread.sleep(10)
+
         player.gameMode = org.bukkit.GameMode.CREATIVE
         assertEquals(creativeItems[0], player.inventory.getItem(0))
         assertEquals(creativeItems[1], player.inventory.getItem(1))