RFE: linter for checking yaml files for layout

[yazug]

ran into issue where packages.yml had duplicated packages: entry and a bad branch url
Looking into ways we might be able to easily check/detect issues in CI Check job.

Sample yaml:

============
---
packages:
  - project: foo
packages:
  - project: bar
  - project: blah
============

yamllint does catch the first issue

$ yamllint test.yaml
test.yaml
  5:1       error    duplication of key "packages" in mapping  (key-duplicates)

[yazug]

I wonder if strictyaml might be useful for distroinfo to enforce some schema/linting in the input data

https://pypi.org/project/strictyaml/