Fix token permissions

[anderseknert]

Use read-all at the top level. Not sure if we actually need anything more somewhere, but I guess this is one way to find out.

[srenatus]

I'd expect that release creation through goreleaser might need more. But let's find out? 🤔

[anderseknert]

@srenatus yeah, will push a release this week, so shouldn’t have forgotten about it by then :)

[charlieegan3]

FWIW, I added 34202b5 and 31bee8d to set the permissions to:

permissions:
   # this is needed to create a release
   contents: write
   # this is needed to create artifacts in ghcr
   packages: write

based on the details here: https://docs.github.com/en/actions/using-jobs/assigning-permissions-to-jobs

I'd not have worked this out without trial and error I think!