3. Add new advisory type to `ee/app/graphql/types/query_type.rb`
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## Overview
:information_source: Please note the use the `ee/` in directories and `EE` in code because [advisory data is GitLab EE only feature](https://handbook.gitlab.com/handbook/product/categories/features/#vulnerability-research).
This work item covers adding support for the `ee/app/graphql/types/package_metadata/advisory_type.rb` GraphQL type to `ee/app/graphql/types/query_type.rb` which essentially 'wires up' the GraphQL Resolver and Type so it can actually be used.
## Actions
- [x] Add new `ee/app/graphql/types/package_metadata/advisory_type.rb` GraphQL type to `ee/app/graphql/ee/types/query_type.rb`.
- [x] Add support for the `ee/app/graphql/types/package_metadata/advisory_type.rb` GraphQL type to `ee/spec/graphql/ee/types/query_type_spec.rb` (~~:information_source: NOTE: `ee/spec/graphql/types/query_type_spec.rb` should be `ee/spec/graphql/ee/types/query_type_spec.rb` and will hopefully be fixed by https://gitlab.com/gitlab-org/gitlab/-/work_items/591087 :pray:~~).
- [x] Ensure `advisory()` queries can be performed as mentioned in Section 3. of ADR-0004.
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