The PHPDoc return type of the \Magento\SalesSequence\Model\Sequence::calculateCurrentValue() method should be int, not string

Should be @return int because the result is produced by an arithmetic expression and is always integer.

See also:

• Propose to make the properties of the \Magento\SalesSequence\Model\Sequence class protected instead of private, so to allow the subclasses to access them
• Propose to make the \Magento\SalesSequence\Model\Sequence::calculateCurrentValue() method protected instead of private, so to allow the subclasses to modify it