mock_uss flight outside of all clusters

[BenjaminPelletier]

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report.json is not attached because
It can be found in the artifacts for the failed continuous integration run: https://github.com/interuss/monitoring/actions/runs/7847957424

Test check
Individual flights obfuscation check

Difference from expected behavior
mock_uss should have been behaving nominally, so either there was a bug in mock_uss's clustering algorithm, or there is a bug in the test scenario that falsely reports failure.

Additional context
Screenshot from sequence view artifact:

Upon retest, this test passed so it appears to be an occasional/flaky failure in either the mock_uss behavior or test logic.