zodbtools: Refer to in-tree eggs via ${<name>:egg} not just name

This is similar to d67f382f (wendelin.core: Fix test build 2)
54 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.SlapRunner.ResilienceTest-Master

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

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passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

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failed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

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passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python2

passed SlapOS.Eggs.UnitTest-Master.Python3

passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.Eggs.UnitTest-Master.Python3

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passed SlapOS.SlapRunner.ResilienceTest-Master

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passed SlapOS.SlapRunner.ResilienceTest-Master

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:42

passed SlapOS.SlapRunner.ResilienceTest-Master

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passed SlapOS.SlapRunner.ResilienceTest-Master

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passed SlapOS.SlapRunner.ResilienceTest-Master

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passed SlapOS.SlapRunner.ResilienceTest-Master

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

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failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

00:23:17

passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

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passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

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passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

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failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

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passed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

06:13:40

failed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

15:03:49

failed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

15:03:40