Bump rack from 3.1.14 to 3.1.16

Bumps [rack](https://github.com/rack/rack) from 3.1.14 to 3.1.16.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@v3.1.14...v3.1.16)

---
updated-dependencies:
- dependency-name: rack
  dependency-version: 3.1.16
  dependency-type: indirect
...

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

Author: dependabot[bot]

Gemfile.lock

@@ -19,7 +19,7 @@ GEM
     drb (2.2.1)
     nkf (0.2.0)
     progressbar (1.13.0)
-    rack (3.1.14)
+    rack (3.1.16)
     rackup (2.1.0)
       rack (>= 3)
       webrick (~> 1.8)