Fix hacking rules: H302,H305,H307,H402

Currently, OpenStack Proposal Bot tries to update requirements with
global requirements, while the upgraded hacking has introduced some
new rules which are not fully handled by current code.

This patch fixes some simple rules which are quite straight-forward.

Change-Id: If8334f69fb1ad34fbbd6ad898e0e92eb3f81e95a
Merge "Fix hacking rules: H302,H305,H307,H402"