[MacPorts] #68493: yarn: update to 3.6.4

[MacPorts]

#68493: yarn: update to 3.6.4
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 Reporter:  contextnerror  |      Owner:  jambonrose
     Type:  update         |     Status:  assigned
 Priority:  Normal         |  Milestone:
Component:  ports          |    Version:
 Keywords:                 |       Port:  yarn
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 Currently the yarn port is at the latest version of Yarn Classic. However
 modern yarn has continued development and is now up to 3.6.4, with version
 4 on the way as a release candidate. Development has migrated to
 https://github.com/yarnpkg/berry

 It may be desirable to leave 1.x as an option, possibly a separate port.

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Ticket URL: <https://trac.macports.org/ticket/68493>
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