Treat fingerprinting fixes like other security fixes: trigger TBB release

Proposal: Treat anti-fingerprinting bugfixes like any other security bugfix with regards to prioritization and release management.

For instance, when an anti-fingerprinting fix lands in git, whether as a Tor Button update or as a mere Tor Browser default pref change, this should trigger a new Tor Browser Bundle release incorporating the fix, even if no other component needs updating.

Deanonymizing users through fingerprint leaks is becoming a realistic threat as the advertising industry consolidates and transforms itself into a tracking industry offering advertising as a sort of higher layer service. And we should assume that all kinds of other adversaries are already closely watching the tbb-fingerprinting tag.