TESTS: replace old test suite with the new one

get rid of Bats definitively

test/test_multiple-ports/test_VIRTUAL_PORT.py

@@ -0,0 +1,7 @@
+import pytest
+
+
+def test_answer_is_served_from_chosen_port(docker_compose, nginxproxy):
+    r = nginxproxy.get("http://web.nginx-proxy.tld/port")
+    assert r.status_code == 200
+    assert "answer from port 90\n" in r.text