[py3] Removed filename encoding in file_uploads test

        tdir = tempfile.gettempdir()

        # This file contains chinese symbols and an accented char in the name.

        with open(os.path.join(tdir, UNICODE_FILENAME.encode('utf-8')), 'w+b') as file1:

        with open(os.path.join(tdir, UNICODE_FILENAME), 'w+b') as file1:

            file1.write(b'b' * (2 ** 10))

            file1.seek(0)