Provide secrets/passwords management for Tor Browser Nightly signing
As mentioned in legacy/trac#34121 (moved), the Tor Browser Nightly signing machine will host an OpenPGP key and an NSSDB private key. Both of these should be password-protected. Instead of hard-coding these passphrases in a file or script on the server, having a password management system from where the passwords can be retrieved would be very nice.