Cannot upload files to epics using REST API
Summary
When adding attachments to issue notes, we have to upload the file to the related project and then inject the resulting markdown into the note. Epics have their own notes, but there appears to be no facility for uploading files to an epic or to the parent group. If I try to upload to a project, the resulting markdown and URL returned is relative to that project, not to the entire system, so when I try to use it in the epic it results in a bad link.
Steps to reproduce
Upload a file to a project using https://docs.gitlab.com/ee/api/projects.html#upload-a-file and try to reference the file in a note on a group epic.
Example Project
n/a
What is the current bug behavior?
It is not possible to upload files with the REST API at the group level or epic.
What is the expected correct behavior?
Either uploads should be tied to the individual notes, or group upload functionality should be exposed with the API.