chore(cleanup): Delete sentiment feature (#9304)

- The feature is unused, removing it for now, will bring it back with better models later.

spec/enterprise/models/conversation_spec.rb

@@ -36,36 +36,6 @@ RSpec.describe Conversation, type: :model do
     # end
   end
 
-  describe 'conversation sentiments' do
-    include ActiveJob::TestHelper
-
-    let(:conversation) { create(:conversation, additional_attributes: { referer: 'https://www.chatwoot.com/' }) }
-
-    before do
-      10.times do
-        message = create(:message, conversation_id: conversation.id, account_id: conversation.account_id, message_type: 'incoming')
-        message.update(sentiment: { 'label': 'positive', score: '0.4' })
-      end
-    end
-
-    it 'returns opening sentiments' do
-      sentiments = conversation.opening_sentiments
-      expect(sentiments[:label]).to eq('positive')
-    end
-
-    it 'returns closing sentiments if conversation is not resolved' do
-      sentiments = conversation.closing_sentiments
-      expect(sentiments).to be_nil
-    end
-
-    it 'returns closing sentiments if it is resolved' do
-      conversation.resolved!
-
-      sentiments = conversation.closing_sentiments
-      expect(sentiments[:label]).to eq('positive')
-    end
-  end
-
   describe 'sla_policy' do
     let(:account) { create(:account) }
     let(:conversation) { create(:conversation, account: account) }