Bump puma from 4.3.6 to 4.3.8

Bumps [puma](https://github.com/puma/puma) from 4.3.6 to 4.3.8.
- [Release notes](https://github.com/puma/puma/releases)
- [Changelog](https://github.com/puma/puma/blob/master/History.md)
- [Commits](https://github.com/puma/puma/compare/v4.3.6...v4.3.8)

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

Gemfile

@@ -44,7 +44,7 @@ gem "paperclip", "~> 6.1.0"
 gem "paranoia", "~> 2.4.2"
 gem "pg", "~> 1.0.0"
 gem "pg_search", "~> 2.3.5"
-gem "puma", "~> 4.3.6"
+gem "puma", "~> 4.3.8"
 gem "recipient_interceptor", "~> 0.2.0"
 gem "redcarpet", "~> 3.5.1"
 gem "responders", "~> 3.0.1"

Gemfile.lock

@@ -450,7 +450,7 @@ GEM
       pronto (~> 0.11.0)
       scss_lint (~> 0.43, >= 0.43.0)
     public_suffix (4.0.6)
-    puma (4.3.6)
+    puma (4.3.8)
       nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)
@@ -744,7 +744,7 @@ DEPENDENCIES
   pronto-eslint (~> 0.11.0)
   pronto-rubocop (~> 0.11.0)
   pronto-scss (~> 0.11.0)
-  puma (~> 4.3.6)
+  puma (~> 4.3.8)
   rails (= 5.2.4.5)
   rails-assets-leaflet!
   rails-assets-markdown-it (~> 9.0.1)!