fix(ui): race condition when setting hf token and downloading model

I ran into a race condition where I set a HF token and it was valid, but
somehow this error toast still appeared. The conditional feel through to
an assertion that we never expected to get to, which crashed the UI.

Handled the unexpected case gracefully now.

Author: psychedelicious

invokeai/frontend/web/src/services/events/onModelInstallError.tsx

@@ -173,14 +173,21 @@ const HFUnauthorizedToastDescription = () => {
   if (data === 'unknown') {
     return (
       <Text fontSize="md">
-        {t('modelManager.hfTokenUnableToErrorMessage')}{' '}
+        {t('modelManager.hfTokenUnableToVerifyErrorMessage')}{' '}
         <Button onClick={onClick} variant="link" color="base.50" flexGrow={0}>
           {t('modelManager.modelManager')}.
         </Button>
       </Text>
     );
   }
 
-  // data === 'valid' - should never happen!
-  assert(false, 'Unexpected valid HF token with unauthorized error');
+  // data === 'valid' - user may have a token but not authorized for model?
+  return (
+    <Text fontSize="md">
+      {t('modelManager.hfTokenForbiddenErrorMessage')}{' '}
+      <Button onClick={onClick} variant="link" color="base.50" flexGrow={0}>
+        {t('modelManager.modelManager')}.
+      </Button>
+    </Text>
+  );
 };