fix: #2537 - index out of range

[Gnoale]

Fixes #2537

Description

It seems that the addendums slice index is incremented twice in cases there is an empty layer in the history

I am not sure to understand what I am doing but here is an attempt to fix it :)

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[aaron-prindle]

Thanks for the PR here @Gnoale, the change you have made here is actually a change against the https://github.com/google/go-containerregistry project. Can you submit this PR there stating that it fixes google/go-containerregistry#1646? Going to close this PR as it is actually an issue with the go-containerregistry library