frontend: only update addbuyreceiveonemptybalance state if mounted

Used mounted hook to only update AddBuyReceiveOnEmptyBalances state
if the component is actually mounted.

This was an approach to fix unknown account code error that
appears doing the following:

1) unlock device
2) navigate to account
3) back to account summary
4) unplug the device

Removing the device sometimes errors in AddBuyReceiveOnEmptyBalances
component.

When logging deciveIDs, keystores and accounts (in sidebar.tsx), it
seems after unplugging the device the keystore is already empty but
the frontend still has accounts for a short time.

Author: thisconnect

frontends/web/src/routes/account/info/buyReceiveCTA.tsx

@@ -22,6 +22,7 @@ import { Balances } from '../summary/accountssummary';
 import { isBitcoinCoin } from '../utils';
 import { getExchangeSupportedAccounts } from '../../buy/utils';
 import styles from './buyReceiveCTA.module.css';
+import { useMountedRef } from '../../../hooks/mount';
 
 type TBuyReceiveCTAProps = {
   balanceList?: [string, IBalance][];
@@ -62,12 +63,20 @@ export const BuyReceiveCTA = ({ code, unit, balanceList, exchangeBuySupported =
 
 
 export const AddBuyReceiveOnEmptyBalances = ({ balances, accounts }: TAddBuyReceiveOnEmpyBalancesProps) => {
-
+  const mounted = useMountedRef();
   const [supportedAccounts, setSupportedAccounts] = useState<IAccount[]>();
 
   useEffect(() => {
-    getExchangeSupportedAccounts(accounts).then(setSupportedAccounts);
-  }, [accounts]);
+    if (mounted.current) {
+      getExchangeSupportedAccounts(accounts)
+        .then(supportedAccounts => {
+          if (mounted.current) {
+            setSupportedAccounts(supportedAccounts);
+          }
+        })
+        .catch(console.error);
+    }
+  }, [accounts, mounted]);
 
   if (balances === undefined || supportedAccounts === undefined) {
     return null;