Bump puma from 4.3.8 to 4.3.12

Bumps [puma](https://github.com/puma/puma) from 4.3.8 to 4.3.12.
- [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/v4.3.8...v4.3.12)

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

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

Gemfile.lock

@@ -145,7 +145,7 @@ GEM
     mini_portile2 (2.8.0)
     minitest (5.14.1)
     multi_json (1.13.1)
-    nio4r (2.5.2)
+    nio4r (2.5.8)
     nokogiri (1.13.4)
       mini_portile2 (~> 2.8.0)
       racc (~> 1.4)
@@ -158,7 +158,7 @@ GEM
       activerecord (>= 5.2.1)
     popper_js (1.14.5)
     public_suffix (4.0.6)
-    puma (4.3.8)
+    puma (4.3.12)
       nio4r (~> 2.0)
     racc (1.6.0)
     rack (2.2.3)