0cc7cbc36d
As per the community goal of migrating the policy file the format from JSON to YAML[1], we need to do two things: 1. Change the default value of '[oslo_policy] policy_file'' config option from 'policy.json' to 'policy.yaml' with upgrade checks. 2. Deprecate the JSON formatted policy file on the project side via warning in doc and releasenotes. Also convert manila/tests/policy.json to manila/tests/policy.yaml using oslopolicy-convert-json-to-yaml tool and replace policy.json to policy.yaml ref from doc and tests. [1]https://governance.openstack.org/tc/goals/selected/wallaby/migrate-policy-format-from-json-to-yaml.html Change-Id: I3748313912b2527c43c9b16a6ba3e3ccd4cf5221