Add test for the agent fact 'implementation'

(cherry picked from commit ae363fc)

Author: Felix Frank

spec/unit/node/facts_spec.rb

@@ -35,6 +35,12 @@
       @facts.add_local_facts
       expect(@facts.values["environment"]).to eq("foo")
     end
+
+    it "adds the implementation fact" do
+      @facts.add_local_facts
+      expect(@facts.values).to include("implementation")
+      expect(@facts.values["implementation"]).to eq("openvox")
+    end
   end
 
   describe "when sanitizing facts" do