Add mainnet NFT token access to membership portal and remove testnet access

[willyogo]

Once we're done testing in testnet and ready to deploy to prod, we should replace the testnet NFT access from the token gate and grant access to holders of the mainnet NFT.

AC:

1. Testnet ATXNouns NFT holders can no longer get through the tokengate
2. Hodlers of mainnet ATXNouns NFTs can get through the tokengate

Reference:
#21