gnu: Remove sky.

This package, along with other SCUMMVM-based games violate the FSDG: they are
neither built from nor point towards their corresponding source code.
See <https://lists.gnu.org/archive/html/guix-devel/2022-08/msg00039.html>
and <https://lists.gnu.org/archive/html/guix-devel/2023-06/msg00091.html>
for more information.

* gnu/packages/games.scm (sky): Delete variable.

gnu/packages/games.scm

@@ -9724,92 +9724,6 @@ (define-public harmonist
 on items and player adaptability for character progression.")
     (license license:isc)))
 
-(define-public sky
-  (package
-    (name "sky")
-    (version "1.2")                     ;1.3 is floppy version
-    (source
-     (origin
-       (method url-fetch)
-       (uri (string-append "mirror://sourceforge/scummvm/extras/"
-                           "Beneath%20a%20Steel%20Sky/"
-                           "bass-cd-" version ".zip"))
-       (sha256
-        (base32 "14s5jz67kavm8l15gfm5xb7pbpn8azrv460mlxzzvdpa02a9n82k"))))
-    (build-system trivial-build-system)
-    (arguments
-     `(#:modules ((guix build utils))
-       #:builder
-       (begin
-         (use-modules (guix build utils))
-         (let* ((out (assoc-ref %outputs "out"))
-                (share (string-append out "/share"))
-                (data (string-append share "/" ,name))
-                (apps (string-append share "/applications"))
-                (bin (string-append out "/bin"))
-                (executable (string-append bin "/" ,name))
-                (scummvm (assoc-ref %build-inputs "scummvm")))
-           (let ((unzip (search-input-file %build-inputs "/bin/unzip")))
-             (invoke unzip "-j" (assoc-ref %build-inputs "source")))
-           (let ((doc (string-append share "/doc/bass-" ,version)))
-             (install-file "readme.txt" doc))
-           (for-each (lambda (f) (install-file f data))
-                     (find-files "." "^sky\\."))
-           ;; Build the executable.
-           (mkdir-p bin)
-           (let ((bash (assoc-ref %build-inputs "bash")))
-             (with-output-to-file executable
-               (lambda ()
-                 (format #t "#!~a/bin/bash~%" bash)
-                 (format #t "exec ~a/bin/scummvm -p ~a sky~%" scummvm data))))
-           (chmod executable #o755)
-           ;; Create desktop file.  There is no dedicated
-           ;; icon for the game, so we borrow SCUMMVM's.
-           (mkdir-p apps)
-           (with-output-to-file (string-append apps "/" ,name ".desktop")
-             (lambda _
-               (format #t
-                       "[Desktop Entry]~@
-                       Name=Beneath a Steel Sky~@
-                       GenericName=Bass~@
-                       Exec=~a~@
-                       Icon=~a/share/icons/hicolor/scalable/apps/scummvm.svg~@
-                       Categories=AdventureGame;Game;RolePlaying;~@
-                       Keywords=adventure;game;roleplaying;cyberpunk;~@
-                       Comment=A science-fiction adventure game set in a bleak post-apocalyptic vision of the future~@
-                       Comment[de]=Ein Science-Fiction-Abenteuerspiel \
-angesiedelt in einer düsteren, postapokalyptischen Vision der Zukunft~@
-                       Type=Application~%"
-                       executable scummvm)))
-           #t))))
-    (native-inputs
-     (list unzip))
-    (inputs
-     (list bash scummvm))
-    (home-page "https://www.scummvm.org/")
-    (synopsis "Classic 2D point and click science-fiction adventure game")
-    (description
-     "Beneath a Steel Sky is a science-fiction thriller set in a bleak
-post-apocalyptic vision of the future.  It revolves around Union City,
-where selfishness, rivalry, and corruption by its citizens seems to be
-all too common, those who can afford it live underground, away from
-the pollution and social problems which are plaguing the city.
-
-You take on the role of Robert Foster, an outcast of sorts from the
-city since a boy who was raised in a remote environment outside of
-Union City simply termed ``the gap''.  Robert's mother took him away
-from Union City as a child on their way to ``Hobart'' but the
-helicopter crashed on its way.  Unfortunately, Robert's mother died,
-but he survived and was left to be raised by a local tribe from the
-gap.
-
-Years later, Union City security drops by and abducts Robert, killing
-his tribe in the process; upon reaching the city the helicopter taking
-him there crashes with him escaping, high upon a tower block in the
-middle of the city.  He sets out to discover the truth about his past,
-and to seek vengeance for the killing of his tribe.")
-    (license (license:non-copyleft "file:///readme.txt"))))
-
 (define-public gnurobots
   (package
     (name "gnurobots")