Updated expired references to signing keys

[fabriziofiorucci]

Proposed changes

Updated expired references to signing keys

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[github-actions]

✅ All required contributors have signed the F5 CLA for this PR. Thank you!
_{Posted by the CLA Assistant Lite bot.}

[fabriziofiorucci]

I have hereby read the F5 CLA and agree to its terms

[mjang]

Ah, these are "public" keys which can be exposed.