refactor(multichain): use ternary in getMaybeSelectedInternalAccount

Co-authored-by: Gustavo Antunes <[email protected]>

ui/selectors/selectors.js

@@ -331,7 +331,7 @@ export function getMaybeSelectedInternalAccount(state) {
   // Same as `getSelectedInternalAccount`, but might potentially be `undefined`:
   // - This might happen during the onboarding
   const accountId = state.metamask.internalAccounts?.selectedAccount;
-  return accountId && state.metamask.internalAccounts?.accounts[accountId];
+  return accountId ? state.metamask.internalAccounts?.accounts[accountId] : undefined;
 }
 
 export function getSelectedInternalAccount(state) {