Add Cost Factored Storage Sizes to GraphQL Project Statistics Type

What does this MR do and why?

Add cost factored storage sizes to the GraphQL project statistics type for each of repositories, build artifacts, LFS files, packages, snippets, and the wiki.

This makes the cost factored storage sizes available to GraphQL queries. We will use this information on the project usage quotas page.

Issue: https://gitlab.com/gitlab-org/gitlab/-/issues/416097

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.