[MacPorts] #64369: Add livecheck.user_agent (was: Add fetch.user_agent)

[MacPorts]

#64369: Add livecheck.user_agent
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  Reporter:  ryandesign   |      Owner:  (none)
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  base         |    Version:  2.7.1
Resolution:               |   Keywords:
      Port:               |
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Ticket URL: <https://trac.macports.org/ticket/64369#comment:1>
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