Bump puma from 4.3.12 to 5.6.9

Bumps [puma](https://github.com/puma/puma) from 4.3.12 to 5.6.9.
- [Release notes](https://github.com/puma/puma/releases)
- [Changelog](https://github.com/puma/puma/blob/master/History.md)
- [Commits](puma/puma@v4.3.12...v5.6.9)

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

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

Gemfile

@@ -8,7 +8,7 @@ gem 'rails', '~> 5.2.1'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3'
 # Use Puma as the app server
-gem 'puma', '~> 4.3'
+gem 'puma', '~> 5.6'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets

Gemfile.lock

@@ -120,7 +120,7 @@ GEM
       mini_portile2 (~> 2.4.0)
     orm_adapter (0.5.0)
     public_suffix (4.0.6)
-    puma (4.3.12)
+    puma (5.6.9)
       nio4r (~> 2.0)
     pwa (4.0.5)
       mozaic (~> 2.0)
@@ -232,7 +232,7 @@ DEPENDENCIES
   devise
   jbuilder (~> 2.5)
   listen (>= 3.0.5, < 3.2)
-  puma (~> 4.3)
+  puma (~> 5.6)
   pwa (~> 4.0.5)
   rails (~> 5.2.1)
   sass-rails (~> 5.0)