Add a security policy to all repositories in @gohugoio

[davidsneighbour]

See #8073 - this repo (and probably the others too) have no security policy set up. It's as easy as adding a SECURITY.md to the repo-root. I propose to do that in all gohugo repositories. A sample I always use quick and dirty on my own repos: https://github.com/dnb-hugo/garuda/blob/main/SECURITY.md

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[bep]

PR welcome. Use my email; gmail handles spam beautifully.

[github-actions]

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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.