Clean up docstring on SSLZuulTestCase

Change-Id: I881a81591c86bf6ad91b8a9a9d082a142e031eef
Signed-off-by: Paul Belanger <pabelanger@redhat.com>
diff --git a/tests/base.py b/tests/base.py
index 1fe9739..9a909e7 100755
--- a/tests/base.py
+++ b/tests/base.py
@@ -2710,7 +2710,7 @@
 
 
 class SSLZuulTestCase(ZuulTestCase):
-    """ZuulTestCase but with an but using SSL when possible"""
+    """ZuulTestCase but using SSL when possible"""
     use_ssl = True