[MacPorts] #39832: gecode: update to 4.2.0

[MacPorts]

#39832: gecode: update to 4.2.0
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  Reporter:  l.digaspero@…  |      Owner:  brandon@…
      Type:  update         |     Status:  new
  Priority:  Normal         |  Milestone:
 Component:  ports          |    Version:
Resolution:                 |   Keywords:  haspatch maintainer
      Port:  gecode         |
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Comment (by brandon@…):

 My apologies, spoiled by git and my manual patch chops are a bit rusty.
 Patch replaced. :)

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Ticket URL: <https://trac.macports.org/ticket/39832#comment:4>
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