fix: correct URL of tag relation in pacticipant version resource

lib/pact_broker/api/decorators/version_decorator.rb

@@ -28,7 +28,7 @@ class VersionDecorator < BaseDecorator
 
         link :'pb:tag' do | options |
           {
-            href: pacticipant_url(options.fetch(:base_url), represented.pacticipant) + '/tags/{tag}',
+            href: version_url(options.fetch(:base_url), represented) + '/tags/{tag}',
             title: "Get, create or delete a tag for this pacticipant version",
             templated: true
           }

spec/lib/pact_broker/api/decorators/version_decorator_spec.rb

@@ -42,6 +42,10 @@ module Decorators
           expect(subject[:_links][:'pb:pacticipant']).to eq title: "Pacticipant", name: "Consumer", href: "http://example.org/pacticipants/Consumer"
         end
 
+        it "includes a link to get, create or delete a tag" do
+          expect(subject[:_links][:'pb:tag']).to include href: "http://example.org/pacticipants/Consumer/versions/1.2.3/tags/{tag}", templated: true
+        end
+
         it "includes a list of the tags" do
           expect(subject[:_embedded][:tags]).to be_instance_of(Array)
           expect(subject[:_embedded][:tags].first[:name]).to eq "prod"