erp5: include default port values in schema definitions

tcpv4-port is currently marked as required, define default ports for
convenience.
11 jobs for feat/erp5-schemas in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS.Eggs.UnitTest-Jerome.Python2

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passed SlapOS.Eggs.UnitTest-Jerome.Python3

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passed SlapOS.Eggs.UnitTest-Jerome.Python2

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failed SlapOS.Eggs.UnitTest-Jerome.Python2

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passed SlapOS.Eggs.UnitTest-Jerome.Python2

passed SlapOS.Eggs.UnitTest-Jerome.Python2

00:22:37

passed SlapOS.Eggs.UnitTest-Jerome.Python2

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passed SlapOS.Eggs.UnitTest-Jerome.Python3

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passed SlapOS.Eggs.UnitTest-Jerome.Python3

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passed SlapOS.Eggs.UnitTest-Jerome.Python3

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passed SlapOS.Eggs.UnitTest-Jerome.Python3

00:16:00