Extend end-2-end test with Token and PerunArt deployment and proper withdrawals.

[sebastianst]

The end-2-end test at src/e2e/sdk_remote_integration.spec.ts currently tests NFT minting and trading, but only of an NFT that doesn't actually exist. It also doesn't test withdrawals. And has a few other issues.

• [x] Update the generated operator.cfg so that it deploys the token and nft contracts. You can also remove the unused ResponseDuration parameter (this can actually also be removed in the core repo's operator.Config struct).
  • [x] The operator should automatically register the token contract types ERC20 and ERC721Mintable. However, it might be necessary to still register the actual contract. Check the other tests in the core repo for how to do this... This affects the walkthrough operator.
• [x] Extend the walkthrough operator so that the test users also are prefunded with some PRN (look at the SimSetup for how this can be done). This affects the walkthrough operator.
• [x] Also deposit PRN, not only ETH.
• [x] Change the minting tests to mint PerunArts.
• [x] Change the trading tests to trade PerunArt NFTs for PRN token.
• [x] Add a test at the end where all users withdraw and assert that the users hold the freshly minted NFTs.

Looking at the core generic enclave tests will also help to fill in the gaps.

[ndzik]

Related #79 and #86

[sebastianst]

I agree that it makes sense to also improve the test structure #79 . And #86 is covered by this issue.