[Security] Bump rack-cors from 1.0.3 to 1.0.6 (#12395)

Bumps [rack-cors](https://github.com/cyu/rack-cors) from 1.0.3 to 1.0.6. **This update includes a security fix.**
- [Release notes](https://github.com/cyu/rack-cors/releases)
- [Changelog](https://github.com/cyu/rack-cors/blob/master/CHANGELOG.md)
- [Commits](https://github.com/cyu/rack-cors/compare/v1.0.3...v1.0.6)

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

Gemfile.lock

@@ -461,7 +461,8 @@ GEM
     rack (2.0.7)
     rack-attack (6.1.0)
       rack (>= 1.0, < 3)
-    rack-cors (1.0.3)
+    rack-cors (1.0.6)
+      rack (>= 1.6.0)
     rack-protection (2.0.7)
       rack
     rack-proxy (0.6.5)