[MacPorts] #47592: rev-upgrade should use prefix_unwritable check

[MacPorts]

#47592: rev-upgrade should use prefix_unwritable check
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  Reporter:  mp@…     |      Owner:  neverpanic
      Type:  defect   |     Status:  closed
  Priority:  Not set  |  Milestone:  MacPorts 2.4.0
 Component:  base     |    Version:  2.3.99
Resolution:  fixed    |   Keywords:
      Port:           |
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Changes (by jmroot):

 * milestone:   => MacPorts 2.4.0


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Ticket URL: <https://trac.macports.org/ticket/47592#comment:10>
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