txn_override_causal_consistency.js verifies that commands run by the network_error_and_txn_override.js logic only includes afterClusterTime when the client's session enabled causal consistency. The test requires each test case to declare if it expects retries on transient errors and will fail if retries occur unexpectedly. Transient errors can be triggered by unrelated background activity (e.g. an automatically created index triggering SnapshotUnavailable errors), so instead the test should allow retries in all cases, since this doesn't affect its intended coverage.