[v1.2.9] Discount section not showing in checkout page on M2.3.3 and under version.

Issue: 

We have purchased the Magento 2 One Step Checkout extension v1.2.9 last week and implement it in our staging environment M2.3.3. We facing an issue on the checkout page. Failed to load the discount component. 

Please advise how to fix the issue. Please refer

Solution: 

The issue is due to the incompatibility of the current module's version with Magento 2.3.3 and under versions.

To solve it, please overwrite two files

app/code/Bss/OneStepCheckout/view/frontend/web/js/action/cancel-coupon.js
app/code/Bss/OneStepCheckout/view/frontend/web/js/action/recollect-shipping-rates.js

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