Allow "warning" type protected ranges

[alifeee]

closes #1437

They were not allowed before because:

It seems that when add_protected_range was added it was assumed that editor_users_emails was always required. However, warning ranges do not require (and in fact, cannot contain) emails.

To fix this issue, we:

• change editor_users_emails from and argument to a keyword argument (if it is not changed in position, it should still be usable as an argument)
• add some logic in the code to not pass "editors" if warning_only is set

[lavigne958]

Great change ! Oddly enough the API allows a user to set a protected range with no editors (when providing an actual empty list of editors). 🤔

[alifeee]

yes I wasn't sure what email to put in the test, since it would be different for whoever ran the test.

maybe the email is fetchable from an API somewhere?

[lavigne958]

yes I wasn't sure what email to put in the test, since it would be different for whoever ran the test.

maybe the email is fetchable from an API somewhere?

I don't think it's a problem. Leaving it like this endures it works with no emails too 🙄