AI-5318 Search for malformed 'namespaced' keys in YAML files
This will refuse namespaced top-level keys in Hiera YAML with namespace separators whose length is not 2, i.e:
- foo:bar
- foo::bar:c
- foo::::bar::c
- bar:baz
Please double-check that I don't have to add the file anywhere so it's synced and also that the CWD is the one I expect when I execute the file from Gitlab CI.