deploy: Uncomment guix-hpc3.

This is a followup to 7d08db3f, which
revived guix-hpc3.

* deploy.scm: Uncomment.

deploy.scm

@@ -35,17 +35,14 @@
                         "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIP0yTo+S20dXf0ep0AC7gJ018cL8dsBTZ/z0QkLc9LC7 root@(none)"))))
 
 
-      ;; XXX: guix-hpc3 is still up but we can no longer reconfigure it due
-      ;; to efivarfs returning ENOSPC without any clear recourse (2024-04-30).
-      ;;
-      ;; (machine
-      ;;  (operating-system (load-operating-system "guix-hpc3.scm"))
-      ;;  (environment managed-host-environment-type)
-      ;;  (configuration (machine-ssh-configuration
-      ;;                  (system "x86_64-linux")
-      ;;                  (host-name "guix-hpc3")
-      ;;                  (host-key
-      ;;                   "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIHZQz08uAzQu3+eo4RbDi/Ost/M5wgUihuidfQELM+F5 root@(none)"))))
+      (machine
+       (operating-system (load-operating-system "guix-hpc3.scm"))
+       (environment managed-host-environment-type)
+       (configuration (machine-ssh-configuration
+                       (system "x86_64-linux")
+                       (host-name "guix-hpc3")
+                       (host-key
+                        "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIHZQz08uAzQu3+eo4RbDi/Ost/M5wgUihuidfQELM+F5 root@(none)"))))
 
 
       (machine