* add additional assertions to test to check for tx ordering

* enhance test to handle tx confirmation ID ordering

* increase size of 0th tx to expose race condition

* change approach since the backend does not order txs by nonce

* tidy

* clarify

* Update op-service/txmgr/queue_test.go
Co-authored-by: Sebastian Stammler <seb@oplabs.co>

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Co-authored-by: Sebastian Stammler <seb@oplabs.co>