refactoring: rename SAT class to LiberviaBackend

tests/unit/conftest.py

@@ -21,7 +21,7 @@ from unittest.mock import MagicMock, AsyncMock
 from pytest import fixture
 from twisted.internet import defer
 from twisted.words.protocols.jabber import jid
-from libervia.backend.core.sat_main import SAT
+from libervia.backend.core.sat_main import LiberviaBackend
 from libervia.backend.tools import async_trigger as trigger
 from libervia.backend.core import xmpp
 
@@ -39,7 +39,7 @@ def storage():
     return AsyncMock()
 
 
-class MockSAT(SAT):
+class MockSAT(LiberviaBackend):
 
     def __init__(self, bridge, storage):
         self._cb_map = {}