[MacPorts] #49576: Fix incorrect checksums in GMTK Portfile

[MacPorts]

#49576: Fix incorrect checksums in GMTK Portfile
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  Reporter:  rprogers@…  |      Owner:  macports-tickets@…
      Type:  defect      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:  haspatch maintainer
      Port:  gmtk        |
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Comment (by ryandesign@…):

 You are correct that the portfile should live in only one system: ours.
 MacPorts requires the portfile to be in its repository to function, and it
 is confusing if another copy is maintained separately elsewhere.

 You should never modify a distfile after it's been released. Distfiles
 should be immutable. If you must make changes, release them under a new
 version number. Modifying a distfile after release is what we call a
 [wiki:PortfileRecipes#stealth-updates stealth update]. You must follow
 that recipe now. Just changing the checksums is not sufficient.

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Ticket URL: <https://trac.macports.org/ticket/49576#comment:5>
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