Upload catpkg.json as the first asset to reduce "downtime" of latest-release/catpkg download

https://github.com/BSData/publish-catpkg/blob/9ac644a36c9304586826c2b34fa74fdbcce6cace/action.ps1#L193-L197

But also consider whether that wouldn't mean users will get the catpkg but then fail with download of files.

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Alternative? Upload previous release's catpkg as the first step, so that while we create and upload other assets, users are redirected to previous release's data.

Then we prioritize upload of everything except catpkg, which would be last and replace the placeholder uploaded at the beginning.