Add GraphQL field `latest_version` to CiCatalogResource

What does this MR do and why?

Added the latest_version field to ciCatalogResource in GraphQL. The latest version of a catalog resource is a Release object.

A new type Ci::Catalog::Resource::VersionType was created which inherits from ReleaseType; the only difference is that VersionType overrides the :read_release authorization. The Release authorization is not required since the user is already authorized through the CiCatalogResource type. If we leave it in, it would cause an N+1 query issue as each resource's latest version (i.e Release) would have to be authorized.

This MR partially resolves #407382 (closed). Also note that there is a follow-up issue to move the latest_versions_by_project_id query into the Release finder: #409712 (closed).

Data Context:

• A Catalog Resource has a 1:1 relationship with Project.
• A Project's "Releases" are equivalent to the Catalog Resource's "Versions".

How to set up and validate locally

1. In the Rails console, run Feature.enable(:ci_private_catalog_beta) and then Feature.enable(:ci_namespace_catalog_experimental).
2. Create a Catalog Resource with an existing or new Project:

::Ci::Catalog::Resource.create(project: Project.find(<project_id>))

3. Ensure that the Project has a non-empty description and also has a README file. (This is required for you to successfully create a Release on the Catalog Resource.)
4. Create at least one Tag and one Release on the Project. (Note that the latest Release is equivalent to the "latest version" of the Catalog Resource.)
5. Go to http://gdk.test:3000/-/graphql-explorer and run the following query (adjust the projectPath as necessary):

query getCiCatalogResources {
  ciCatalogResources(projectPath: "group-a/project-catalog-resource-1") {
    nodes {
      id
      name
      latestVersion {
        tagName
        releasedAt
        author {
          id
          name
          webUrl
        }
      }
    }
  }
}

6. Observe that the output shows the correct Catalog Resource information along with the latest version data.

Screenshot

Query Plan

SELECT DISTINCT ON (project_id) * FROM "releases" WHERE "releases"."project_id" IN (7764, 250833, 13083) ORDER BY "releases"."project_id" ASC, "releases"."released_at" DESC

Query Plan Link: https://console.postgres.ai/shared/12860bae-0c37-4bfa-98fe-433b9ac0e0dc

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #407382 (closed)