Binary caching of vcpkg packages

[DanRStevens]

Seems there is a new vcpkg feature designed specifically for GitHub Actions (though is still experimental):
https://learn.microsoft.com/en-us/vcpkg/users/binarycaching#gha

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In the past we've used the NuGet method, with setup for GitHub Actions:
https://learn.microsoft.com/en-us/vcpkg/users/binarycaching#quickstart-github

However, it seems when using the GITUHB_TOKEN credential, the uploaded packages are associated with the repository of the workflow being run, and are only accessible to that repository. This is unfortunate, as the package repository is per organization, not per repository, so if another repository is setup with the same packages to cache, they can't both upload a package with the same name.

Sample workflow run error:
https://github.com/OutpostUniverse/op2-landlord/actions/runs/5395217904/jobs/9797427353

WARNING: Your request could not be authenticated by the GitHub Packages service. Please ensure your access token is valid and has the appropriate scopes configured.

Relevant GitHub documentation:

• https://docs.github.com/en/packages/learn-github-packages/configuring-a-packages-access-control-and-visibility
• https://docs.github.com/en/packages/learn-github-packages/about-permissions-for-github-packages

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Organization package settings:

• https://github.com/organizations/OutpostUniverse/settings/packages

Organization packages:

• https://github.com/orgs/OutpostUniverse/packages