add zone test-rspec

spec/controllers/api/restaurant/zone_controller_spec.rb

@@ -0,0 +1,12 @@
+require 'rails_helper'
+
+RSpec.describe Api::Restaurant::ZoneController, type: :controller do
+
+  describe "GET #index" do
+    it "returns http success" do
+      get :index
+      expect(response).to have_http_status(:success)
+    end
+  end
+
+end