Bump puma from 5.6.2 to 5.6.4

Bumps [puma](https://github.com/puma/puma) from 5.6.2 to 5.6.4.
- [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/v5.6.2...v5.6.4)

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

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

Gemfile.lock

@@ -303,7 +303,7 @@ GEM
     pry-rails (0.3.9)
       pry (>= 0.10.4)
     public_suffix (4.0.6)
-    puma (5.6.2)
+    puma (5.6.4)
       nio4r (~> 2.0)
     pundit (2.2.0)
       activesupport (>= 3.0.0)