Fix H404/405 violations for remaining

There is a lot of H404/405 violations in Tempest now, and that leads
difficult to migrate the code to tempest-lib or the other projects'
repos. This patch fixes these violations for remaining.

Change-Id: I3abac40ebb33836980c119d59bc97f035b213c0a
diff --git a/tox.ini b/tox.ini
index 09c8626..892cfed 100644
--- a/tox.ini
+++ b/tox.ini
@@ -129,6 +129,6 @@
 # E123 skipped because it is ignored by default in the default pep8
 # E129 skipped because it is too limiting when combined with other rules
 # Skipped because of new hacking 0.9: H405
-ignore = E125,E123,E129,H404,H405
+ignore = E125,E123,E129
 show-source = True
 exclude = .git,.venv,.tox,dist,doc,openstack,*egg