[MacPorts] #23125: libpng: update to 1.4.x, tweak livecheck (was: graphics/libpng update version, tweak livecheck)

[MacPorts]

#23125: libpng: update to 1.4.x, tweak livecheck
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  Reporter:  rmsfisher@…             |       Owner:  ryandesign@…           
      Type:  update                  |      Status:  closed                 
  Priority:  Normal                  |   Milestone:                         
 Component:  ports                   |     Version:                         
Resolution:  fixed                   |    Keywords:                         
      Port:  libpng                  |  
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Ticket URL: <https://trac.macports.org/ticket/23125#comment:19>
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