Point web frontend to belvedere temporarily

While we're figuring out the next steps for the disk space on beaubourg / somerset, we should repoint the web app to the main database.

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Migrated from T2562 (view on Phabricator)

marked this issue as related to #2561 (closed)

added System administration priority:High labels

deployed.

closed

mentioned in issue swh/devel/swh-web#2557 (closed)