gregistrysettingsbackend: Remove translatable pspec nick/blurb

The file was not listed in `POTFILES.in` (as pointed out by Piotr Drąg
in
fee0a7679a (note_1722885)),
so either it needs to be added to `POTFILES.in` or the translatable
strings need to be removed.

Recent prior art from GTK shows that there’s actually no longer any
point in setting the nick/blurb as no tools use them (and if they did,
it would result in a rubbish user experience). See
https://gitlab.gnome.org/GNOME/gtk/-/issues/4904.

Hence, drop the strings entirely.

See #2991 for tracking this across all of GIO.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

Helps: #2991

gio/gregistrysettingsbackend.c

@@ -2319,8 +2319,7 @@ g_registry_settings_backend_class_init (GRegistrySettingsBackendClass *class)
   g_object_class_install_property (object_class,
                                    PROP_REGISTRY_KEY,
                                    g_param_spec_string ("registry-key",
-                                                        P_("Root registry key"),
+                                                        NULL, NULL,
-                                                        P_("The path to the registry key where settings are stored"),
                                                         "HKEY_CURRENT_USER\\Software\\GSettings",
                                                         G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
                                                         G_PARAM_STATIC_STRINGS));