qa: fix test_getServerAddress (testCMFActivity)

With recent changes in CMFActivity, getServerAddress is now used
when setting up the site, before the ZServer is started, which means:
- getServerAddress memoized a wrong return value;
- the test didn't fail with --load.

product/CMFActivity/tests/testCMFActivity.py

@@ -2455,15 +2455,8 @@ class TestCMFActivity(ERP5TypeTestCase, LogInterceptor):
     self.assertEqual(activity_node, current_node)
 
   def test_getServerAddress(self):
-    ip = port = ''
-    for k, v in socket_map.items():
-      if hasattr(v, 'addr'):
-        type = str(getattr(v, '__class__', 'unknown'))
-        if type == 'ZServer.HTTPServer.zhttp_server':
-          ip, port = v.addr
-          break
-    if ip == '0.0.0.0':
-      ip = socket.gethostbyname(socket.gethostname())
+    host, port = self.startZServer()
+    ip = socket.gethostbyname(host)
     server_address = '%s:%s' % (ip, port)
     address = getServerAddress()
     self.assertEqual(address, server_address)

product/ERP5Type/tests/ProcessingNodeTestCase.py

@@ -158,6 +158,13 @@ class ProcessingNodeTestCase(ZopeTestCase.TestCase):
         t = Thread(target=Lifetime.loop)
         t.setDaemon(1)
         t.start()
+      from Products.CMFActivity import ActivityTool
+      # Reset, in case that getServerAddress was already called,
+      # in which case, the value was ('', '')
+      if ActivityTool._server_address:
+        if ActivityTool.currentNode == ActivityTool._server_address:
+          ActivityTool.currentNode = None
+        ActivityTool._server_address = None
     return utils._Z2HOST, utils._Z2PORT
 
   def _registerNode(self, distributing, processing):