NEO: fix stress test against recent zodbtools update

See commit e83edfc9.
6 jobs for jm in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS.SlapRunner.ResilienceTest-Master

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

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passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

03:42:19