Description of the problem, including code/CLI snippet

Following snippet only fetches the first page.

p = gl.projects.get("gitlab-org/gitlab-ce")
all_mrs = p.mergerequests.list(state="all", order_by="updated_at", as_list=False)
for mr in all_mrs:
    print(all_mrs.current_page, all_mrs.total_pages)

Expected Behavior

should fetch all pages

Actual Behavior

only display current_page = 1, while it should go through 994 pages.

works as expected on pypi version.

Specifications

• python-gitlab version: master
• API version you are using (v3/v4): v4
• Gitlab server version (or gitlab.com): gitlab.com