Bump rack-attack from 6.0.0 to 6.1.0 (#11313)

Bumps [rack-attack](https://github.com/kickstarter/rack-attack) from 6.0.0 to 6.1.0.
- [Release notes](https://github.com/kickstarter/rack-attack/releases)
- [Changelog](https://github.com/kickstarter/rack-attack/blob/master/CHANGELOG.md)
- [Commits](https://github.com/kickstarter/rack-attack/compare/v6.0.0...v6.1.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Gemfile

@@ -67,7 +67,7 @@ gem 'ox', '~> 2.11'
 gem 'posix-spawn', git: 'https://github.com/rtomayko/posix-spawn', ref: '58465d2e213991f8afb13b984854a49fcdcc980c'
 gem 'pundit', '~> 2.0'
 gem 'premailer-rails'
-gem 'rack-attack', '~> 6.0'
+gem 'rack-attack', '~> 6.1'
 gem 'rack-cors', '~> 1.0', require: 'rack/cors'
 gem 'rails-i18n', '~> 5.1'
 gem 'rails-settings-cached', '~> 0.6'