Add missing natspec

[zajck]

Method createRoyaltyRecipientAccount is missing the documentation

boson-protocol-contracts/contracts/protocol/facets/SellerHandlerFacet.sol

Line 519 in 9ed49d7

function createRoyaltyRecipientAccount(address payable _royaltyRecipient) internal {

• Move it to the end of the file, since it's internal.