Put in missing s2b needed for session list test.

Author: rouilj

test/test_mysql.py

@@ -172,6 +172,8 @@ def tearDown(self):
 from .session_common import SessionTest
 @skip_mysql
 class mysqlSessionTest(mysqlOpener, SessionTest, unittest.TestCase):
+    s2b = lambda x,y : y
+
     def setUp(self):
         mysqlOpener.setUp(self)
         SessionTest.setUp(self)

test/test_postgresql.py

@@ -278,6 +278,8 @@ def tearDown(self):
 from .session_common import SessionTest
 @skip_postgresql
 class postgresqlSessionTest(postgresqlOpener, SessionTest, unittest.TestCase):
+    s2b = lambda x,y : y
+
     def setUp(self):
         postgresqlOpener.setUp(self)
         SessionTest.setUp(self)