Bump puma from 5.6.4 to 6.4.0 (#400)

Bumps [puma](https://github.com/puma/puma) from 5.6.4 to 6.4.0.
- [Release notes](https://github.com/puma/puma/releases)
- [Changelog](https://github.com/puma/puma/blob/master/History.md)
- [Commits](puma/puma@v5.6.4...v6.4.0)

---
updated-dependencies:
- dependency-name: puma
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Gemfile

@@ -3,7 +3,7 @@ git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
 gem 'rails', '~> 6.1'
 gem 'pg', '>= 0.18', '< 2.0'
-gem 'puma', '~> 5.6'
+gem 'puma', '~> 6.4'
 
 gem 'panoptes-client'
 gem 'pundit'

Gemfile.lock

@@ -149,7 +149,7 @@ GEM
       timeout
     net-smtp (0.3.3)
       net-protocol
-    nio4r (2.5.8)
+    nio4r (2.5.9)
     nokogiri (1.13.10)
       mini_portile2 (~> 2.8.0)
       racc (~> 1.4)
@@ -167,7 +167,7 @@ GEM
       pry (~> 0.13.0)
     pry-rails (0.3.9)
       pry (>= 0.10.4)
-    puma (5.6.4)
+    puma (6.4.0)
       nio4r (~> 2.0)
     pundit (2.1.1)
       activesupport (>= 3.0.0)
@@ -279,7 +279,7 @@ DEPENDENCIES
   pg (>= 0.18, < 2.0)
   pry-byebug
   pry-rails
-  puma (~> 5.6)
+  puma (~> 6.4)
   pundit
   pundit-matchers
   rack-cors