Enable hacking H404 test.
Enable hacking H404 test.

H404 - multi line docstring should start with a summary.

Change-Id: I2099e1ee81ff9657f7a07401b8e8f3327d03bdbd

varunarya10/oslo.context,yanheven/oslo.middleware,citrix-openstack-build/oslo.context,openstack/oslo.context,JioCloud/oslo.context,dims/oslo.context