How can I disable the display of subtotal bifurcation based on tax on the shopping cart page?

Before installing the Magento GST extension, you may have set up some tax class and you may be displaying the subtotal bifurcation on cart page based on the set tax class.
Now, after the GST extension is installed and tax class is set to None, you need to stop displaying bifurcated subtotal based on the tax, you can disable it from System > Configuration > Sales > Tax > Shopping Cart Display Settings and set the option “Display Subtotal” from “Including and Excluding Tax” to “Excluding Tax”.