Remove GPL-3.0 from accepted licences

We need to ignore the GPL-3.0 violation for now (if we want to keep using the pallet-contracts), as this is an upstream issue:
https://github.com/paritytech/polkadot-sdk/issues/2708

Alternative: Remove pallet-contracts dependency