Release process: how to tell whether the website has finished building?

While releasing Tails 4.8 I spotted a few issues now that our workflow has been adapted to GitLab:

(Minor annoyance) Now that the final Git push is to GitLab, not gitolite with blocking hooks, it would be nice to have some other way to tell when the website has finished building. Alternatively, perhaps it's enough to just wait until the page containing the version that is built last (https://tails.boum.org/upgrade/win-download/?) is updated?
(moved to !36 (merged))

Edited Jul 01, 2020 by intrigeri

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