Bump puma from 3.12.2 to 3.12.4

Bumps [puma](https://github.com/puma/puma) from 3.12.2 to 3.12.4.
- [Release notes](https://github.com/puma/puma/releases)
- [Changelog](https://github.com/puma/puma/blob/master/History.md)
- [Commits](puma/puma@v3.12.2...v3.12.4)

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

Author: dependabot[bot]

Gemfile.lock

@@ -134,7 +134,7 @@ GEM
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
-    puma (3.12.2)
+    puma (3.12.4)
     rack (2.0.8)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)