docs: public EpicIssue assignIssue(Object groupIdOrPath, Integer epicIid, Integer issueIid) throws GitLabApiException {
          Response response = post(Response.Status.CREATED, (Form)null,
                  "groups", getGroupIdOrPath(groupIdOrPath), "epics", epicIid, "issues", issueIid);
          return (response.readEntity(EpicIssue.class));
      }