The issue is in the oddo 8 taken from git
When we create the product and its related variant.And view the product variant through Product --> variant --> list of variant then it is working fine i.e update the sale price including the baseprice(Product.template) + attribute extra price.
Now when we click on the Product variant sub menu in the side panel and search the variant of the related product its sales price is not updated along with the extra price.

The sales price of product variant (product.product) is updated on the basis of sales price of product(product.template) which is not including the attribute extra price which is defined in the Product(Prduct.template).
So views of the same variant(i.e. 'Product Variant' and 'Product --> vairant -->list of Variant') reflect different sales prices