Force-enable release confirmations for high-target plugins

[dd32]

As a follow up to #5352, we should consider force enabling release confirmations for plugins that meet an undetermined criteria.

Discussion in #5352 suggested:

1. Plugins with over 1 million active installs
2. and with more than 1 committer

1 could be lowered over time if found to be reasonable.

[casiepa]

I suppose a page/post would be needed somewhere first where all committers of all +1mil could be warned? Or would it be just an email to them? (or both?)

[dd32]

This could also be enabled for plugins that feature in the Featured or Beta plugin sections, as they're often not 1m+ but are still highly visible and trusted.