fix: stopgap for BigNumber shift NaN issue (#24691)

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## **Description**
Stopgap for #24690

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## **Related issues**

Related: #24690
– do not close this.

## **Manual testing steps**

1. Try to reproduce
#24690

## **Screenshots/Recordings**

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### **Before**

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### **After**

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ui/pages/confirmations/components/simulation-details/useBalanceChanges.ts

@@ -140,8 +140,9 @@ function getTokenBalanceChanges(
     };
 
     const decimals =
-      asset.standard === TokenStandard.ERC20 && erc20Decimals[asset.address]
-        ? erc20Decimals[asset.address]
+      // TODO(dbrans): stopgap for https://github.com/MetaMask/metamask-extension/issues/24690
+      asset.standard === TokenStandard.ERC20
+        ? erc20Decimals[asset.address] ?? ERC20_DEFAULT_DECIMALS
         : 0;
     const amount = getAssetAmount(tokenBc, decimals);