This commit migrate all event trigger policies into code [1].
Like oslo.config, with oslo.policy, we can define all of
default rules in code base and only change some rules
via policy file. Another thing that we should use yaml
format instead of json format.
This commit also remove policy.json file usage completely.
[1] https://governance.openstack.org/tc/goals/queens/policy-in-code.html
Co-authored-By: Dai Dang-Van <daidv@vn.fujitsu.com>
Change-Id: Icd674fdc248e5b9c63f9e7d0f47c53288291ff07
4469cacf39