Bump rack from 2.2.3 to 2.2.6.4 (#109)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -126,7 +126,7 @@ GEM
     nokogiri (1.13.10-x64-mingw32)
       racc (~> 1.4)
     racc (1.6.1)
-    rack (2.2.3)
+    rack (2.2.6.4)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (6.1.5)