Resync the metadata for an NFT

• The metadata flag will request the NFT's metadata from an already existing token_uri
• The uri (default) flag will fetch the latest token_uri from the given NFT contract address. In sync mode the metadata will also be fetched
• The sync mode will make the endpoint synchronous so it will wait for the task to be completed before responding
• The async mode (default) will make the endpoint asynchronous so we will wait for the task to be completed before responding