Bump puma from 5.3.1 to 5.6.4

Bumps [puma](https://github.com/puma/puma) from 5.3.1 to 5.6.4.
- [Release notes](https://github.com/puma/puma/releases)
- [Changelog](https://github.com/puma/puma/blob/master/History.md)
- [Commits](puma/puma@v5.3.1...v5.6.4)

---
updated-dependencies:
- dependency-name: puma
  dependency-type: direct:production
...

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

Gemfile

@@ -8,7 +8,7 @@ gem 'rails', '~> 6.1.0', '>= 6.1.0.0'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3', '~> 1.4'
 # Use Puma as the app server
-gem 'puma', '~> 5.3'
+gem 'puma', '~> 5.6'
 # Use SCSS for stylesheets
 gem 'sass-rails', '>= 6'
 # Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker

Gemfile.lock

@@ -133,14 +133,14 @@ GEM
     minitest (5.14.4)
     multi_json (1.15.0)
     multi_xml (0.6.0)
-    nio4r (2.5.7)
+    nio4r (2.5.8)
     nokogiri (1.11.5-x86_64-darwin)
       racc (~> 1.4)
     nokogiri (1.11.5-x86_64-linux)
       racc (~> 1.4)
     optimist (3.0.1)
     public_suffix (4.0.6)
-    puma (5.3.1)
+    puma (5.6.4)
       nio4r (~> 2.0)
     puppet (7.12.1)
       concurrent-ruby (~> 1.0)
@@ -283,7 +283,7 @@ DEPENDENCIES
   gitable
   hiera-eyaml
   listen (~> 3.2)
-  puma (~> 5.3)
+  puma (~> 5.6)
   puppet
   puppetdb-ruby
   rails (~> 6.1.0, >= 6.1.0.0)