Bump puma from 6.3.1 to 6.4.0

Bumps [puma](https://github.com/puma/puma) from 6.3.1 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@v6.3.1...v6.4.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -111,9 +111,9 @@ GEM
       coderay (~> 1.1)
       method_source (~> 1.0)
       spoon (~> 0.0)
-    puma (6.3.1)
+    puma (6.4.0)
       nio4r (~> 2.0)
-    puma (6.3.1-java)
+    puma (6.4.0-java)
       nio4r (~> 2.0)
     racc (1.7.1)
     racc (1.7.1-java)