Have boum.org deploy staging.tails.boum.org

Originally created by @sajolida on #9186 (Redmine)

Once we solved all the blockers, we should ask boum.org to deploy this website.

Parent Task: sysadmin#9183 (closed)

Related issues

• Blocked by sysadmin#9184 (closed)
• Blocked by sysadmin#9185 (closed)
• Blocks sysadmin#9187 (closed)