Refactor ERC165 to use function overriding instead of storage (#2505)

Co-authored-by: Francisco Giordano <frangio.1@gmail.com>

contracts/mocks/ERC165Mock.sol

@@ -5,7 +5,4 @@ pragma solidity ^0.8.0;
 import "../introspection/ERC165.sol";
 
 contract ERC165Mock is ERC165 {
-    function registerInterface(bytes4 interfaceId) public {
-        _registerInterface(interfaceId);
-    }
 }