Bump puma from 6.4.2 to 6.4.3 in /examples/rails

Bumps [puma](https://github.com/puma/puma) from 6.4.2 to 6.4.3.
- [Release notes](https://github.com/puma/puma/releases)
- [Changelog](https://github.com/puma/puma/blob/master/History.md)
- [Commits](puma/puma@v6.4.2...v6.4.3)

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

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

examples/rails/Gemfile

@@ -9,7 +9,7 @@ ruby '~> 3.0'
 gem 'rails', '~> 6.0'
 
 # Server
-gem 'puma', '~> 6.4.2'
+gem 'puma', '~> 6.4.3'
 
 # Messaging via GCP Pub/Sub
 gem 'cloudenvoy', path: '../../'

examples/rails/Gemfile.lock

@@ -162,13 +162,13 @@ GEM
       timeout
     net-smtp (0.4.0.1)
       net-protocol
-    nio4r (2.7.0)
+    nio4r (2.7.3)
     nokogiri (1.16.7)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     os (1.1.4)
     public_suffix (5.0.4)
-    puma (6.4.2)
+    puma (6.4.3)
       nio4r (~> 2.0)
     racc (1.8.1)
     rack (2.2.9)
@@ -233,7 +233,7 @@ PLATFORMS
 
 DEPENDENCIES
   cloudenvoy!
-  puma (~> 6.4.2)
+  puma (~> 6.4.3)
   rails (~> 6.0)
   sqlite3