[MacPorts] #38708: py-astropy: use external, MacPorts cfitsio, expat, and wcslib; drop redundant python.default_version

[MacPorts]

#38708: py-astropy: use external, MacPorts cfitsio, expat, and wcslib; drop
redundant python.default_version
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  Reporter:  aronnax@…    |      Owner:  robitaille@…
      Type:  enhancement  |     Status:  closed
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:  fixed        |   Keywords:
      Port:  py-astropy   |
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Comment (by robitaille@…):

 Sorry for not checking this sooner - It looks like this has caused
 buildbot failures, did you receive those @aronnax?

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Ticket URL: <https://trac.macports.org/ticket/38708#comment:4>
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