Restore UDFs removed by buggy merges

wiki/src/upgrade/v2/Tails/4.12/amd64/alpha/upgrades.yml

+---
+build-target: amd64
+channel: alpha
+initial-install-version: '4.12'
+product-name: Tails

wiki/src/upgrade/v2/Tails/4.12/amd64/alpha/upgrades.yml.pgp

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