Implement Non Fungible Token Royalty (EIP2981) (#3012)

Co-authored-by: Francisco Giordano <frangio.1@gmail.com>
Co-authored-by: Hadrien Croubois <hadrien.croubois@gmail.com>

contracts/mocks/ERC721RoyaltyMock.sol

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.0;
+
+import "../token/ERC721/extensions/ERC721Royalty.sol";
+
+contract ERC721RoyaltyMock is ERC721Royalty {
+    constructor(string memory name, string memory symbol) ERC721(name, symbol) {}
+
+    function setTokenRoyalty(
+        uint256 tokenId,
+        address recipient,
+        uint96 fraction
+    ) public {
+        _setTokenRoyalty(tokenId, recipient, fraction);
+    }
+
+    function setDefaultRoyalty(address recipient, uint96 fraction) public {
+        _setDefaultRoyalty(recipient, fraction);
+    }
+
+    function mint(address to, uint256 tokenId) public {
+        _mint(to, tokenId);
+    }
+
+    function burn(uint256 tokenId) public {
+        _burn(tokenId);
+    }
+
+    function deleteDefaultRoyalty() public {
+        _deleteDefaultRoyalty();
+    }
+}