For Newton, the content of the page needs to be updated to reflect the
change from .JSON to YAML format. A note also needs to be added that
specifies environments with .JSON format policy files will still work
through a backport.
Change-Id: I11c5f2b8e5964e37ae9fb04e2bd2260cd6a5b6d2
Co-Authored-By: Kevin_Zheng <zhengzhenyu@huawei.com>
Closes-Bug: #1575926