Update InstancedTexture.cpp

Performance optimization to skip iterating over the whole thing.

src/Engine/types/InstancedTexture.cpp

@@ -15,9 +15,12 @@ void InstancedTexture::RemoveUser(const InstancedSprite* user) {
 }
 
 bool InstancedTexture::InUseBy(const InstancedSprite* rhs) {
-    for (const auto* u : users)
-        if (u == rhs)
-            return true;
+    if (users.empty())
+        return false;
+
+    if (typeid(*users[0]) == typeid(*rhs))
+        return true;
+
     return false;
 }