[MacPorts] #61317: py38-cartopy needs update to version 0.18

[MacPorts]

#61317: py38-cartopy needs update to version 0.18
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  Reporter:  jolivetr    |      Owner:  (none)
      Type:  update      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  py-cartopy  |
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Comment (by mf2k):

 In the future, please add the port maintainer(s) to Cc ({{{port info
 --maintainers py-cartopy}}}), if any.

 You can [wiki:WorkingWithGit#pr submit a GitHub pull request].

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Ticket URL: <https://trac.macports.org/ticket/61317#comment:1>
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