Add ca-certificates as deps for trixie

.github/workflows/check_repos.yml

@@ -62,7 +62,7 @@ jobs:
       - name: Add packages.freedom.press PGP key (sq)
         if: matrix.version == 'trixie'
         run: |
-          apt-get update && apt-get install -y sq
+          apt-get update && apt-get install -y ca-certificates sq
           mkdir -p /etc/apt/keyrings/
           # On debian trixie, apt-secure uses `sqv` to verify the signatures
           # so we need to retrieve PGP keys and store them using the base64 format.