Fix Updater only restarting sys-* qubes

After an update to qubes-vm-update [1] (which the SDW updater uses
under the hood) `--restart` was changed to only restart `sys-*`
qubes. The new qubes-vm-update flag --apply-to-all has the behavior
we intend.

Fixes #1127

[1]: QubesOS/qubes-core-admin-linux@93078d0b

sdw_updater/Updater.py

@@ -159,7 +159,7 @@ def apply_updates_templates(templates=current_templates, progress_callback=None)
 def _start_qubes_updater_proc(templates):
     update_cmd = [
         "qubes-vm-update",
-        "--restart",  # Enforce app qube restarts
+        "--apply-to-all",  # Enforce app qube restarts
         "--show-output",  # Update transaction details (goes to stdout)
         "--just-print-progress",  # Progress reporting (goes to stderr)
         "--targets",