chore: Use Round Robin service for team assignment (#4237)

Co-authored-by: Pranav Raj S <pranav@chatwoot.com>

spec/controllers/api/v1/accounts/conversations/assignments_controller_spec.rb

@@ -35,6 +35,9 @@ RSpec.describe 'Conversation Assignment API', type: :request do
       end
 
       it 'assigns a team to the conversation' do
+        team_member = create(:user, account: account, role: :agent)
+        create(:inbox_member, inbox: conversation.inbox, user: team_member)
+        create(:team_member, team: team, user: team_member)
         params = { team_id: team.id }
 
         post api_v1_account_conversation_assignments_url(account_id: account.id, conversation_id: conversation.display_id),
@@ -44,6 +47,8 @@ RSpec.describe 'Conversation Assignment API', type: :request do
 
         expect(response).to have_http_status(:success)
         expect(conversation.reload.team).to eq(team)
+        # assignee will be from team
+        expect(conversation.reload.assignee).to eq(team_member)
       end
     end