Remove eth_sign and eth_signTransaction

[antondalgren]

It would be reasonable to remove the support for these methods (eth_sign, eth_signTransaction) due to security reasons to not incentivise wallet developers and dApp developers to use these methods out in the wild. We must currently add exceptions to our supported list of methods to be able to test our wallet integration with the dApp.

References:

• eth_sign https://twitter.com/CT_IOE/status/1534658825843683328
• eth_signTransaction https://github.com/MetaMask/metamask-extension/issues/2506 https://github.com/MetaMask/metamask-extension/issues/3475

An alternative would be to make it possible to select what methods you want to send in the sessionProposal from the react-app to the wallet.