Bump rack-attack from 6.2.1 to 6.2.2 (#12681)

Bumps [rack-attack](https://github.com/kickstarter/rack-attack) from 6.2.1 to 6.2.2.
- [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/v6.2.1...v6.2.2)

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

Gemfile.lock

@@ -459,7 +459,7 @@ GEM
       activesupport (>= 3.0.0)
     raabro (1.1.6)
     rack (2.0.8)
-    rack-attack (6.2.1)
+    rack-attack (6.2.2)
       rack (>= 1.0, < 3)
     rack-cors (1.1.0)
       rack (>= 2.0.0)