test_setup_soldr_cache_keys.py::test_suffixes_are_unique_per_runner fails on main #1623

Seen while running the setup-soldr v0 canary (#1613, closed and not for merge).

ci/test_setup_soldr_cache_keys.py::test_suffixes_are_unique_per_runner fails on fbuild main (70e08e3) as well as on the canary branch. It has nothing to do with the setup-soldr pin. The canary's CI passed without it.

Expected. Each runner's setup-soldr cache-key suffix is unique, or the test is updated to match the intended key scheme.