Describe the bug

When testing portfolio, i remove all the exchanges from select exchanges and KeyError occurred causing select tokens to not work

Workaround: User can still refresh the page and will display again ✅

Steps to reproduce bug

1. Setup hummingbot/deploy with ./setup.sh
2. Add connectors on Credentials page
3. On Portfolio, click x on the Select Exchanges next Select Accounts
   • On Select Accounts, add your account again e.g master_account
   • Observed Select token does not display any of each connectors selected