make campaign-status accessible without login

[zouharvi]

• Removes @login_required, making campaign-status accessible even without a login. Tested that it still works if someone is logged in and is is_staff.
• Removes sort_key arguments since it's not being used anywhere.

[snukky]

Technically, sort_key is used if provided in the URL after last /:

Appraise/Appraise/urls.py

Line 192 in 1118cf2

r'(?P<sort_key>[0123456])?/?$',

If it works, that's fine for now. I'm unsure if we can drop the login requirement beyond WMT entirely, but let's not bother with it at the moment neither. Thanks!