Use variant-dependent variable to make URLs for vanishing

[whym]

Description (required)

This is a follow up to #6098.

I made it work for the beta flavor, and updated the URLs for vanishing.

Here are rationales for the change:

• According to https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CentralAuth/+/1043328 the URL Special:Contact/accountvanishapps seems to be the old one. It redirects Special:AccountVanishRequest probably for backwards compatibility. We can use the redirect target directly.
• I think we don't have to use Meta - English Wikipedia uses en.wikipedia.org instead of meta.wikimedia.org . It seems to work for Commons, too. https://en.wikipedia.org/wiki/Wikipedia:Courtesy_vanishing#How_to_request_a_courtesy_vanishing
  I believe the old contact URL only worked for meta.wikimedia.org (which is still the case for other types of Special:Contact/xyz). It is not the case for the new URL, apparently.

Tests performed (required)

• Tested betaDebug on emulator (API 35) - the vanishing request page on Beta Commons loaded.
• Tested prodDebug on emulator (API 35) - the vanishing request page on Commons loaded.

After this testing, my beta account is pending approval for the vanishing. It seems that less people are monitoring Beta Commons, if someone is doing it at all. If it won't get actually renamed, I think getting it in the pending stage is enough for testing the beta flavor.

I stopped before proceeding to request vanishing at this time for production.

[whym]

Actually, according to https://phabricator.wikimedia.org/T380527 it might be better to use Meta until the logging issue is resolved.

EDIT: Local endpoints continue to be available, too. So both Meta-Wiki and Commons endpoints would be fine.

Should we still use the Meta-Wiki URLs? That can be accommodated, if needed.

[sivaraam]

Should we still use the Meta-Wiki URLs? That can be accommodated, if needed.

Is there a particular reason you suggest to still use Meta-wiki? Do you say that because the Wikipedia app uses it?

[whym]

Do you say that because the Wikipedia app uses it?

The fact that T380527 (linked above) is not resolved might be another (small) reason - I think by using Meta-Wiki the lock as a result of vanishing will be logged on Meta-Wiki, too. Apparently the global community likes that, although I would expect local communities don't mind either way. Realistically I expect few people look at those automated locks anyway.

[sivaraam]

Ok. It's fine to use the Meta-wiki for now, I suppose. But how would it work for the beta cluster? Should just use the local wiki there in case beta does not have a corresponding meta wiki?

[whym]

There is a Meta wiki in the beta cluster. The URL is meta.wikimedia.beta.wmflabs.org instead of commons.wikimedia.beta.wmflabs.org. Everything seems to work like the production wikis (except that vanishing requests seem to be perpetually pending).

[whym]

I added a variable for the meta wiki URL.

As for the tests, I did the same.

Tested betaDebug on emulator (API 35) - the vanishing request page on Beta Commons loaded.
Tested prodDebug on emulator (API 35) - the vanishing request page on Commons loaded.

I added a comment that we (presumably) can use the local URL after T380527 is resolved, too.