I tried to use #+INCLUDE "sitemap.org" :only-contents t with the
:auto-sitemap option on my publishing project, but whenever I include a
file this way the title appends to the exported document title.

example file (test.org)

```
#+TITLE: My title

#+INCLUDE "sitemap.org" :only-contents t
```

Now the exported document title test.html contains the title: My title
Sitemap
Expected behaviour: the title I set with #+TITLE

Why is orgmode doingt such "smart" things for me?