build(deps): bump rack from 2.2.9 to 3.1.7

Bumps [rack](https://github.com/rack/rack) from 2.2.9 to 3.1.7.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@v2.2.9...v3.1.7)

---
updated-dependencies:
- dependency-name: rack
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Gemfile

@@ -9,7 +9,7 @@ ruby File.read(".ruby-version").rstrip
 gem "activesupport"
 gem "config"
 gem "mechanize"
-gem "rack", "< 3"
+gem "rack", "< 4"
 gem "roda"
 gem "sidekiq"
 gem "slack-ruby-client"

Gemfile.lock

@@ -108,7 +108,7 @@ GEM
       method_source (~> 1.0)
     public_suffix (6.0.0)
     racc (1.8.0)
-    rack (2.2.9)
+    rack (3.1.7)
     rainbow (3.1.1)
     rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
@@ -181,7 +181,7 @@ DEPENDENCIES
   guard
   guard-rspec
   mechanize
-  rack (< 3)
+  rack (< 4)
   roda
   rspec (~> 3.12)
   rubocop