Add support for policy test definitions

[jsoriano]

What does this PR do?

Add definitions for policy tests. These tests can be used to check that for a given user configuration the expected policies are generated.

Why is it important?

Cover the gap of testing the package policies generated for a given configuration. This is kind of tested in system tests, but these new tests will allow to check the expected policies and more easily add more test cases, without needing a fully running system.

Checklist

• [x] I have added test packages to test/packages that prove my change is effective.
• [x] I have added an entry in spec/changelog.yml.

Related issues

• Part of https://github.com/elastic/elastic-package/issues/947
• Required for https://github.com/elastic/elastic-package/pull/1847

[jsoriano]

CI failure unrelated, to be fixed in https://github.com/elastic/package-spec/pull/752.

[elasticmachine]

:green_heart: Build Succeeded

• Buildkite Build
• Commit: dba5b38d53a1108bd11b9da416699b62b04df4a4

History

• :broken_heart: Build #664 failed bf3a63d13e3e9b6a543847e730bb3889e84f6126

cc @jsoriano