feat: add specs for missing configuration

spec/enterprise/models/account_spec.rb

@@ -120,6 +120,15 @@ RSpec.describe Account, type: :model do
       end
     end
 
+    describe 'captain limits are not configured' do
+      it 'returns default values' do
+        account.custom_attributes = { 'plan_name': 'unknown' }
+        expect(account.captain_monthly_limit).to eq(
+          { documents: ChatwootApp.max_limit, generated_responses: ChatwootApp.max_limit }.with_indifferent_access
+        )
+      end
+    end
+
     describe 'audit logs' do
       it 'returns audit logs' do
         # checking whether associated_audits method is present