Fix: swap GITHUB_TOKEN for GH_PAT

[webgtx]

You can't use default GITHUB_TOKEN if you want to push container to ghcr, you need to use Personal Access Token instead.

Don't forget to add a new secret, and configure scopes for your personal token.

[CLAassistant]

All committers have signed the CLA.

[bep]

Thanks, but your statement is not true. I have pushed several images with the default token; the problem is that the workflow does not trigger on tags produced by the GitHub release UI.

[webgtx]

@bep You're right, sorry for the false PR. If think you need PAT only for private registries/repositories