datasette: link_or_copy_directory() error - Invalid cross-device link

Hi, when I run

datasette  publish heroku -n myapp --template-dir ./template mydb.db

I have this error

Traceback (most recent call last):
  File "/home/aborruso/.local/lib/python3.7/site-packages/datasette/utils/__init__.py", line 607, in link_or_copy_directory
    shutil.copytree(src, dst, copy_function=os.link)
  File "/usr/lib/python3.7/shutil.py", line 365, in copytree
    raise Error(errors)
shutil.Error: [('/myfolder/youtubeComunePalermo/processing/./template/base.html', '/tmp/tmps9_4mzc4/templates/base.html', "[Errno 18] Invalid cross-device link: '/myfolder/youtubeComunePalermo/processing/./template/base.html' -> '/tmp/tmps9_4mzc4/templates/base.html'"), ('/myfolder/youtubeComunePalermo/processing/./template/index.html', '/tmp/tmps9_4mzc4/templates/index.html', "[Errno 18] Invalid cross-device link: '/myfolder/youtubeComunePalermo/processing/./template/index.html' -> '/tmp/tmps9_4mzc4/templates/index.html'")]

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/aborruso/.local/bin/datasette", line 8, in <module>
    sys.exit(cli())
  File "/home/aborruso/.local/lib/python3.7/site-packages/click/core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "/home/aborruso/.local/lib/python3.7/site-packages/click/core.py", line 782, in main
    rv = self.invoke(ctx)
  File "/home/aborruso/.local/lib/python3.7/site-packages/click/core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/aborruso/.local/lib/python3.7/site-packages/click/core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/aborruso/.local/lib/python3.7/site-packages/click/core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/aborruso/.local/lib/python3.7/site-packages/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/home/aborruso/.local/lib/python3.7/site-packages/datasette/publish/heroku.py", line 103, in heroku
    extra_metadata,
  File "/usr/lib/python3.7/contextlib.py", line 112, in __enter__
    return next(self.gen)
  File "/home/aborruso/.local/lib/python3.7/site-packages/datasette/publish/heroku.py", line 191, in temporary_heroku_directory
    os.path.join(tmp.name, "templates"),
  File "/home/aborruso/.local/lib/python3.7/site-packages/datasette/utils/__init__.py", line 609, in link_or_copy_directory
    shutil.copytree(src, dst)
  File "/usr/lib/python3.7/shutil.py", line 321, in copytree
    os.makedirs(dst)
  File "/usr/lib/python3.7/os.py", line 221, in makedirs
    mkdir(name, mode)
FileExistsError: [Errno 17] File exists: '/tmp/tmps9_4mzc4/templates'

I’m attaching my very basic template folder.

Thank you

template.zip