generate-cask-ci-matrix.rb: better ci-skip-repository coverage

[pthariensflame]

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Make sure that ci-skip-repository also skips Forgejo audits and archived repository audits. Unblocks Homebrew/homebrew-cask#252371.

[pthariensflame]

@bevanjkay Here is the requested PR.

[bevanjkay]

Thank you @pthariensflame