Don't log password arguments of keystone module

Set no_log=True for the 'login_password' and 'password' arguments of the
keystone module so that they will not be printed in plain text within
Ansible run output.

Change-Id: I07748e9ff1c1459f0eacf1409bef4e158c9e6446

library/keystone

@@ -1302,7 +1302,8 @@ def main():
                 required=False
             ),
             login_password=dict(
-                required=False
+                required=False,
+                no_log=True
             ),
             login_tenant_name=dict(
                 required=False
@@ -1317,7 +1318,8 @@ def main():
                 required=False
             ),
             password=dict(
-                required=False
+                required=False,
+                no_log=True
             ),
             endpoint=dict(
                 required=True,