feat: lock webrick to ~>1.3.1

Webrick >= 1.4.0 requires ruby >= 2.3.0, and Travelling Ruby is only available for ruby 2.2

Author: bethesque

packaging/Gemfile

@@ -4,3 +4,4 @@ gem "pact"
 gem "pact-mock_service"
 gem "pact-provider-verifier"
 gem "pact_broker-client"
+gem "webrick", "~> 1.3.1"

packaging/Gemfile.lock

@@ -88,7 +88,7 @@ GEM
       tins (~> 1.0)
     thor (0.20.0)
     tins (1.16.3)
-    webrick (1.4.2)
+    webrick (1.3.1)
 
 PLATFORMS
   ruby
@@ -98,6 +98,7 @@ DEPENDENCIES
   pact-mock_service
   pact-provider-verifier
   pact_broker-client
+  webrick (~> 1.3.1)
 
 BUNDLED WITH
    1.15.4