[MacPorts] #60553: github portgroup default non-default livecheck values interfere with one another

[MacPorts]

#60553: github portgroup default non-default livecheck values interfere with one
another
------------------------+------------------------
 Reporter:  ryandesign  |      Owner:  ryandesign
     Type:  defect      |     Status:  assigned
 Priority:  Normal      |  Milestone:
Component:  ports       |    Version:  2.6.2
 Keywords:              |       Port:  github
------------------------+------------------------
 It is common for a portfile to offer both a stable version of the software
 and a development version in a -devel subport, and although it was not
 originally intended to use the github portgroup in this way, many ports
 have taken to invoking `github.setup` both in the main port and the -devel
 subport (with different values for the version field). In this case it is
 desired for the main port's livecheck to return the latest tagged version
 and the -devel port's livecheck to return the latest tag on the applicable
 branch. I feel like this used to work but it got broken at some point,
 requiring ports to use workarounds like
 [6a97ae2a383a43097c8b1b18ebf3d8aa877a6eba/macports-ports] which were not
 supposed to be necessary.

 The portgroup used to overwrite the livecheck variables whenever
 `github.setup` was invoked but some of them were changed from overwrites
 to defaults in [8c8cfbced424311973717d48f0193ad4e53820a3/macports-ports]
 and [17f5c7000ffae20fe396789d21db3aa5b8ae6dda/macports-ports]. Using
 defaults was necessary to implement those features because those livecheck
 variables are now based on other variables that the user is allowed and
 expected to overwrite after `github.setup` has been invoked. Hopefully the
 fix is as simple as making all of the livecheck variables defaults rather
 than overwrites.

-- 
Ticket URL: <https://trac.macports.org/ticket/60553>
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