Add support for attributes to the ERC721NFTs contract

[Dr-Electron]

Is your feature request related to a problem? Please describe.

As discussed on Discord and Slack, we should extend the work of this PR to also allow attributes in the same way as part of the json

Describe the solution you'd like

tokenUri should also return the IRC27 attributes (if they exist) as part of the JSON. Like the opensea standard linked above describes it

Describe alternatives you've considered

On Slack doing some ERC-7496 magic was mentioned.