Use current class name on super call

In order to get the method resolution correct for setUp in the tests we
need to call super on the current Class not the parent.

Change-Id: I1cf7f45c107a1fad2b70e3b18dc23b8bcc6c4b33
diff --git a/tests/unit/test_nodepool.py b/tests/unit/test_nodepool.py
index 0f23c9e..610c2bc 100644
--- a/tests/unit/test_nodepool.py
+++ b/tests/unit/test_nodepool.py
@@ -27,7 +27,7 @@
     # scheduler.
 
     def setUp(self):
-        super(BaseTestCase, self).setUp()
+        super(TestNodepool, self).setUp()
 
         self.zk_chroot_fixture = self.useFixture(
             ChrootedKazooFixture(self.id()))