build(deps): bump rack from 2.2.2 to 2.2.3 in /samples/rails_app

Bumps [rack](https://github.com/rack/rack) from 2.2.2 to 2.2.3.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/master/CHANGELOG.md)
- [Commits](rack/rack@v2.2.2...2.2.3)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

samples/rails_app/Gemfile.lock

@@ -3,7 +3,6 @@ PATH
   specs:
     imagekitio (1.0.0)
       carrierwave (>= 0.7, < 2.2)
-      rails (~> 5.2.0, >= 5.2.0)
       rest-client (~> 2.1, >= 2.1)
 
 GEM
@@ -101,7 +100,7 @@ GEM
       domain_name (~> 0.5)
     i18n (1.8.2)
       concurrent-ruby (~> 1.0)
-    image_processing (1.10.3)
+    image_processing (1.11.0)
       mini_magick (>= 4.9.5, < 5)
       ruby-vips (>= 2.0.17, < 3)
     io-like (0.3.1)
@@ -121,7 +120,7 @@ GEM
     method_source (1.0.0)
     mime-types (3.3.1)
       mime-types-data (~> 3.2015)
-    mime-types-data (3.2019.1009)
+    mime-types-data (3.2020.0512)
     mimemagic (0.3.4)
     mini_magick (4.10.1)
     mini_mime (1.0.2)
@@ -137,7 +136,7 @@ GEM
       method_source (~> 1.0)
     public_suffix (4.0.3)
     puma (3.12.4)
-    rack (2.2.2)
+    rack (2.2.3)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (5.2.4.2)
@@ -216,7 +215,7 @@ GEM
       execjs (>= 0.3.0, < 3)
     unf (0.1.4)
       unf_ext
-    unf_ext (0.0.7.6)
+    unf_ext (0.0.7.7)
     web-console (3.7.0)
       actionview (>= 5.0)
       activemodel (>= 5.0)