Snowbridge test fixes

[claravanstaden]

Updates Snowbridge Kusama and Polkadot runtime integration tests. Todo:

• update updated helper methods in runtime tests (Resolves Replace Snowbridge test helper methods once polkadot-sdk 1.8.0 has been released #234)
• create agent and create channel tests should pass

[claravanstaden]

@ggwpez I have fixed the Snowbridge integration tests and also updated the runtime tests. I don't directly know what's happening here: https://github.com/Snowfork/runtimes/blob/snowbridge-test-fixes/integration-tests/emulated/tests/assets/asset-hub-polkadot/src/tests/reserve_transfer.rs#L477 But I can have a look at it in a separate PR, this PR is just focused on the Snowbridge tests.

[ggwpez]

All fixed, great 🙏

I have fixed the Snowbridge integration tests and also updated the runtime tests. I don't directly know what's happening here: https://github.com/Snowfork/runtimes/blob/snowbridge-test-fixes/integration-tests/emulated/tests/assets/asset-hub-polkadot/src/tests/reserve_transfer.rs#L477 But I can have a look at it in a separate PR, this PR is just focused on the Snowbridge tests.

I will check what part i deleted there