Follow up: Remove HTTP logic from Danger rule after we move to a single codebase

Once we have moved to a single codebase, we won't need to do an HTTP API in the ce_ee_vue_templates Danger rule as implemented in https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/27328.

This issue serves as a reminder to simplify this rule after we have moved to a single codebase.