Fix the unit test error and adjust the condition for fetching objects #1236

Job	Run time
ci (release)	13m 13s
ci (unit-tests)	17m 13s
ci (e2e-tests-airflow-integration)	16m 22s
ci (e2e-tests-assembly-local)	18m 40s
ci (e2e-tests-assembly-distributed)	19m 54s
ci (e2e-tests-autogenerated-helm-chart)	18m 52s
ci (e2e-tests-failover)	18m 35s
ci (e2e-tests-repartition-dask)	20m 15s
ci (e2e-tests-schedule-workflow)	17m 8s
ci (e2e-tests-schedule-workflow-without-crd)	16m 14s
ci (e2e-tests-schedule-workload)	14m 41s
ci (e2e-tests-serialize)	15m 35s
ci (e2e-tests-sidecar)	16m 29s
ci (e2e-tests-spill)	15m 4s
ci (e2e-tests-workflow)	15m 58s
ci (e2e-tests-mars-examples)	11m 2s
ci (e2e-tests-vineyardctl)	16m 38s
ci (e2e-tests-deploy-raw-backup-and-recover)	16m 44s
	4h 58m 37s

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