[MacPorts] #59834: Boost: update to 1.74.0

[MacPorts]

#59834: Boost: update to 1.74.0
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  Reporter:  michaelld  |      Owner:  (none)
      Type:  update     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:
      Port:  boost      |
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Old description:

> Boost 1.74.0 was released on 20200814 <
> https://www.boost.org/users/history/version_1_74_0.html >
>
> I've closed the WIP PR for 1.72.0 because it was stale. I'll do a local
> update / test to work on compatibility and if things aren't horrible then
> I'll create another PR. Hopefully this Boost is more project-compatible
> than the prior 2 versions, and so we can get it in place more quickly.

New description:

 Boost 1.74.0 was released on 20200814 <
 https://www.boost.org/users/history/version_1_74_0.html >

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Comment (by michaelld):

 I've closed the WIP PR for 1.72.0 because it was stale. I'll do a local
 update / test to work on compatibility and if things aren't horrible then
 I'll create another PR. Hopefully this Boost is more project-compatible
 than the prior 2 versions, and so we can get it in place more quickly.

-- 
Ticket URL: <https://trac.macports.org/ticket/59834#comment:5>
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