imp(testing): use testing.TB instead of testing.T

[fedekunze]

Description

Currently, the testing package only supports unit testing through testing.T. This PR refactors the ibc testing package to support testing.B (benchmarks) and testing.F (fuzz) tests.

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[fedekunze]

tests failures seem to be unrelated

[damiannolan]

tests failures seem to be unrelated

sometimes e2e tests will fail intermittently with docker network related errors, I wouldn't worry about it.
I kicked off the failing test to run again.

[damiannolan]

🙏

[colin-axner]

Thanks @fedekunze!