Remove superfluous test.py

Use `./setup.py test`

test.py

-#!/usr/bin/env python3
-# ~*~ coding: utf-8 ~*~
-#-
-# Copyright © 2021
-#       mirabilos <m@mirbsd.org>
-#
-# Provided that these terms and disclaimer and all copyright notices
-# are retained or reproduced in an accompanying document, permission
-# is granted to deal in this work without restriction, including un‐
-# limited rights to use, publicly perform, distribute, sell, modify,
-# merge, give away, or sublicence.
-#
-# This work is provided “AS IS” and WITHOUT WARRANTY of any kind, to
-# the utmost extent permitted by applicable law, neither express nor
-# implied; without malicious intent or gross negligence. In no event
-# may a licensor, author or contributor be held liable for indirect,
-# direct, other damage, loss, or other issues arising in any way out
-# of dealing in the work, even if advised of the possibility of such
-# damage or existence of a defect, except proven that it results out
-# of said person’s immediate fault when using the work as intended.
-
-from test.test_musicxml import *
-from test.test_parser import *
-from test.test_playlist import *
-
-unittest.main()