test: fix flaky test in account-token-list.spec.js (#23450)

## **Description**

Reason of flakiness is race condition: we assert value as soon as we
found the element, the real value has not been rendered


## **Related issues**

Fixes: #23451

## **Manual testing steps**

Run test multiple times with `yarn test:e2e:single --browser=chrome
test/e2e/tests/settings/account-token-list.spec.js`

## **Screenshots/Recordings**

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before and after of your change. -->

### **Before**

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### **After**

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test/e2e/tests/settings/account-token-list.spec.js

@@ -23,6 +23,7 @@ describe('Settings', function () {
         const tokenListAmount = await driver.findElement(
           '[data-testid="multichain-token-list-item-value"]',
         );
+        await driver.waitForNonEmptyElement(tokenListAmount);
         assert.equal(await tokenListAmount.getText(), tokenValue);
 
         await driver.clickElement('[data-testid="account-menu-icon"]');