Rewrite `ibc-test::timeout-refund` in Python

[Fraser999]

We should change the just recipe timeout-refund from inline bash in charts/just/run/ibc-test.just to invoking a new Python test provided in the system-tests folder.

We should use and extend as necessary the existing helper types and functions in system-tests.

[joroshiba]

This issue is stale because it has been open 45 days with no activity. Remove stale label or this issue
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[joroshiba]

This issue was closed because it was stale