Update to v4.2.8

CHANGELOG.md

Gemfile.lock

SECURITY.md

app/javascript/packs/admin.jsx

app/mailers/admin_mailer.rb

app/services/activitypub/process_account_service.rb

app/services/verify_link_service.rb

app/views/admin/settings/registrations/show.html.haml

app/views/admin_mailer/auto_close_registrations.text.erb

app/workers/scheduler/auto_close_registrations_scheduler.rb

config/locales/en.yml

config/settings.yml

config/sidekiq.yml

docker-compose.yml

lib/mastodon/version.rb

spec/models/setting_spec.rb

spec/rails_helper.rb

spec/services/activitypub/process_account_service_spec.rb

spec/services/verify_link_service_spec.rb

spec/spec_helper.rb