cleanup: Remove gnome-shell-extension-prefs wrapper

After the old tool transformed into the extensions app, we added
a wrapper for compatibility with extensions that spawned the
command to open their preferences.

This was a long time ago.

As the ESM port happened since, we *know* that all extensions
are newer than that change. And as spawning the old prefs tool
is no longer accepted in review, no extension that is compatible
with current shell versions still does it.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3456>

src/gnome-shell-extension-prefs

@@ -1,31 +0,0 @@
-#!/bin/sh
-
-openPrefs() {
-  if [ "$(which gnome-extensions)" ]
-  then
-    gnome-extensions prefs $1
-  else
-    gdbus call --session \
-      --dest=org.gnome.Shell.Extensions \
-      --object-path=/org/gnome/Shell/Extensions \
-      --method=org.gnome.Shell.Extensions.OpenExtensionPrefs $1 '' '{}'
-  fi
-}
-
-cat >&2 <<EOT
-gnome-shell-extension-prefs is deprecated
-
-Install https://flathub.org/apps/details/org.gnome.Extensions for extension
-management, or use the gnome-extensions command line tool.
-
-Extensions can use the ExtensionUtils.openPrefs() method.
-EOT
-
-UUID=$1
-
-if [ "$UUID" ]
-then
-  openPrefs $UUID
-else
-  gapplication launch org.gnome.Extensions
-fi

src/meson.build

@@ -43,10 +43,6 @@ if get_option('extensions_tool')
   )
 endif
 
-install_data('gnome-shell-extension-prefs',
-  install_dir: bindir
-)
-
 typelib_cflags = [
   '-DMUTTER_TYPELIB_DIR="@0@"'.format(mutter_typelibdir),
   '-DSHELL_TYPELIB_DIR="@0@"'.format(pkglibdir),