[Backport] Floating point overflows in checkout totals fixed

[suryakant-krish]

Original Pull Request

#18185

Description

Round the total amount to 4 decimal places in \Magento\Quote\Model\Quote\Address\Total::setTotalAmount, to avoid floating point overflows

Fixed Issues (if relevant)

1. Cart Total is NaN in some circumstances #18027: Cart Total is NaN in some circumstances
2. ...

Manual testing scenarios

1. Put two items in the cart, in our case this is one product at 59,80€ incl. Tax and one product at 9,49€ incl. Tax, Shipping is free
2. Apply a coupon code (cart price rule) with 100% discount
3. This usually results in a floating point overflow and the grand total coming as 1.4210854715202e-14 instead of 0
4. After this fix, the grand total should come 0

[magento-engcom-team]

Hi @suryakant-krish. Thank you for your contribution
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[milindsingh]

Duplicate #20638

[sivaschenko]

Thanks for the port @suryakant-krish , however, let's collaborate to deliver earlier port PR. Closing this pull request as a duplicate to #20638

[ghost]

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