Update IP for test

test_gandi_ddns.py

 import gandi_ddns as script
-import socket
+import requests
 
 def test_get_ip():
-    assert script.get_ip() == socket.gethostbyname(socket.gethostname())
+    assert script.get_ip() == requests.get("http://ipecho.net/plain?").text
\ No newline at end of file