Migrate ink-waterfall tests to e2e tests

[ascjones]

Currently the ink-waterfall does not work, see paritytech/ink-waterfall#41 and polkadot-js/apps#8364.

We need to have continued confidence that all our examples are working.

Let's migrate all the waterfall tests to be E2E tests in this repo. This is just a list of all files from https://github.com/paritytech/ink-waterfall/tree/819b12969a068de10b7984e5ce9957f79a0a53a7/src/tests.

Let's share the load and migrate them one-by one:

• set_code_hash.rs
• contract_terminate.rs Migrate contract-terminate waterfall test to e2e #1511
• data_structures.rs
• trait_incrementer.rs
• trait_erc20.rs
• erc721.rs
• contract_transfer.rs
• seal_code_hash.rs**
• seal_ecdsa.rs
• contract_introspection.rs
• incrementer.rs**
• erc1155.rs
• multisig.rs
• dns.rs
• trait_flipper.rs
• rand_extension.rs
• flipper.rs Migrate flipper waterfall test to e2e #1573
• delegator.rs
• forward_calls.rs
• erc20.rs Migrate erc20 waterfall test to e2e #1513