Upgrade Tor Browser to 9.0.9
Originally created by @CyrilBrulebois on #17594 (Redmine)
This matches Firefox ESR 68.7.
Due to the pending planned release (4.5), we didn’t go for an emergency release (4.4.2) to ship Tor Browser 9.0.8, which itself was based on Firefox ESR 68.6.1 (https://www.mozilla.org/en-US/security/advisories/mfsa2020-11/).