This test starts two transactions. It then starts a collection drop, which will block behind the transactions. It confirms the drop has a pending X lock by running find commands until one times out. Finally, it waits for the transactions to expire and the drop to succeed (transactionLifetimeLimitSeconds was reduced to 10).
However, depending on the timing of the test, it is possible for the find command not to run until the transactions are about to expire, in which case it can error with QueryPlanKilled when the collection is dropped.
We can just remove the wait for the drop to have a pending X lock. No future test operations rely on the test having a pending X lock. Its purpose is just to confirm that the drop is blocked behind the transactions. However, this can be inferred from the namespaces.