Revert ".guix-authorizations: Remove biscuolo due to inactivity."

The original commit was made mistakenly; I forgot to look at all of our
Git repos, including maintenance.git, when checking for recent activity.

This reverts commit 94521669ed23096f930be68efc691ccb793cc76f.

.guix-authorizations

@@ -25,6 +25,8 @@
   (;; primary: "34FF 38BC D151 25A6 E340  A0B5 3453 2F9F AFCA 8B8E"
    "A0C5 E352 2EF8 EF5C 64CD  B7F0 FD73 CAC7 19D3 2566"
    (name "bavier"))
+  ("45CC 63B8 5258 C9D5 5F34  B239 D37D 0EA7 CECC 3912"
+   (name "biscuolo"))
   ("7988 3B9F 7D6A 4DBF 3719  0367 2506 A96C CF63 0B21"
    (name "boskovits"))
   ("E82A C026 95D6 FF02 43CA  1E5C F6C5 2DD1 BA27 CB87"