fix: pact_broker/Gemfile & pact_broker/Gemfile.lock to reduce vulnerabilities (#75)

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-RUBY-PUMA-2400629

Author: snyk-bot

pact_broker/Gemfile

@@ -2,7 +2,7 @@ source 'https://rubygems.org'
 
 gem "pact_broker"
 gem "pg", "~>1.0"
-gem "puma", "~> 5.5"
+gem "puma", "~> 5.6", ">= 5.6.2"
 gem "mysql2", "~>0.3"
 gem "sqlite3", "~>1.3"
 gem "rake", "~> 13.0"

pact_broker/Gemfile.lock

@@ -111,7 +111,7 @@ GEM
     padrino-support (0.15.1)
     parslet (2.0.0)
     pg (1.3.1)
-    puma (5.6.1)
+    puma (5.6.2)
       nio4r (~> 2.0)
     racc (1.6.0)
     rack (2.2.3)
@@ -173,10 +173,10 @@ DEPENDENCIES
   mysql2 (~> 0.3)
   pact_broker
   pg (~> 1.0)
-  puma (~> 5.5)
+  puma (~> 5.6, >= 5.6.2)
   rake (~> 13.0)
   sqlite3 (~> 1.3)
   webrick (~> 1.6)
 
 BUNDLED WITH
-   2.3.6
+   2.1.4