Fix remove artifacts during map load

lib/mapping/MapFormatH3M.cpp

@@ -925,8 +925,7 @@ void CMapLoaderH3M::loadArtifactsOfHero(CGHeroInstance * hero)
 		logGlobal->debug("Hero %d at %s has set artifacts twice (in map properties and on adventure map instance). Using the latter set...", hero->getHeroTypeID().getNum(), hero->anchorPos().toString());
 
 		hero->artifactsInBackpack.clear();
-		while(!hero->artifactsWorn.empty())
-			hero->removeArtifact(hero->artifactsWorn.begin()->first);
+		hero->artifactsWorn.clear();
 	}
 
 	for(int i = 0; i < features.artifactSlotsCount; i++)