Update e2e tests

[DeshErBojhaa]

Packet forward middleware had their own test setup when they were in ibc-app repo.

Now we are moving them to ibc-go repo. Since ibc-go repo already has good testing framework in-place, we should use the existing testing framework.

[DeshErBojhaa]

This is done here. #8292

In future we will have to cleanup/update e2e tests for PFM. But we have a recent tracker for it #8360