feat: Business hours

Data models and APIs for business hours

ref: #234

spec/models/inbox_spec.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'rails_helper'
+require Rails.root.join 'spec/models/concerns/out_of_offisable_spec.rb'
 
 RSpec.describe Inbox do
   describe 'validations' do
@@ -33,6 +34,10 @@ RSpec.describe Inbox do
     it { is_expected.to have_many(:hooks) }
   end
 
+  describe 'concerns' do
+    it_behaves_like 'out_of_offisable'
+  end
+
   describe '#add_member' do
     let(:inbox) { FactoryBot.create(:inbox) }
     let(:user) { FactoryBot.create(:user) }