Bump rack-protection from 1.5.3 to 1.5.5

Bumps [rack-protection](https://github.com/sinatra/sinatra) from 1.5.3 to 1.5.5.
- [Release notes](https://github.com/sinatra/sinatra/releases)
- [Changelog](https://github.com/sinatra/sinatra/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sinatra/sinatra/commits)

Author: dependabot[bot]

Gemfile.lock

@@ -13,8 +13,8 @@ GEM
     mime-types (2.99.2)
     netrc (0.11.0)
     puma (2.15.3)
-    rack (1.6.4)
-    rack-protection (1.5.3)
+    rack (1.6.11)
+    rack-protection (1.5.5)
       rack
     rest-client (1.8.0)
       http-cookie (>= 1.0.2, < 2.0)