Remove project and group releases json endpoints

We already have proper API for releases, and API correctly handles guests permissions(not exposing tags).

But currently, frontend uses

• https://gitlab.com/gitlab-org/gitlab/blob/af2320c7637b83525c9419a8263ea20ce2818876/app/controllers/projects/releases_controller.rb#L24
• https://gitlab.com/gitlab-org/gitlab/blob/af2320c7637b83525c9419a8263ea20ce2818876/app/controllers/groups/releases_controller.rb#L10

at least for issues filters(see this issue.

Since 2 endpoints above aren't a public API, we can remove them when fronted stops requesting them.

• Allow guests to see tag names associated with releases

• send an error to sentry if these enpoints are accessed(or find another way to verify they aren't, e.g. use grafana)

• remove these endpoints

This is marked as security because at the moment these endpoint leak information about git tags.