[MacPorts] #34619: prevent use of unknown subports

[MacPorts]

#34619: prevent use of unknown subports
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  Reporter:  ryandesign  |      Owner:  macports-tickets@…
      Type:  defect      |     Status:  closed
  Priority:  Normal      |  Milestone:  MacPorts 2.5.0
 Component:  base        |    Version:  2.1.1
Resolution:  fixed       |   Keywords:
      Port:              |
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Changes (by jmroot):

 * milestone:  MacPorts Future => MacPorts 2.5.0


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Ticket URL: <https://trac.macports.org/ticket/34619#comment:9>
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