Pricing/Resolver/TaxResolver.php
public function resolveSaleTaxRule(SaleInterface $sale): ?TaxRuleInterface
    {
        return $this->resolveTaxRule($this->resolveTargetCountry($sale), $sale->isBusiness());
    }
public function resolveSaleTaxRule(SaleInterface $sale): ?TaxRuleInterface
    {
        return $this->resolveTaxRule($this->resolveTargetCountry($sale), $sale->isBusiness());
    }
Resolves the sale tax rule.

@param SaleInterface $sale

@return TaxRuleInterface|null