Refactor only/except configuration policies
What does this MR do?
This merge request refactors only/except policies so that these policies could be self-contained.
This also adds some changes to YAML configuration library to provide more context to default entry value fabrication process.
What are the relevant issue numbers?
Related to gitlab-org/gitlab-ee#8997
Does this MR meet the acceptance criteria?
-
Tests added for this feature/bug -
Conforms to the code review guidelines -
Security reports checked/validated by reviewer
Edited by Kamil Trzciński