[FIX] bus: watch for changed assets in backend only

Since [1] when the bus service was adapted to wowl, the assets watchdog
service was imported in the frontend. Because the assets will be the
right ones on the next visited page, the notification it might trigger
is seen as degrading the website UX.

This commit removes the assets watchdog service from the frontend
pages.

Steps to reproduce:
- Visit a public page in a tab - keep it open.
- From a different browser, log in and rebuild assets.
=> Notification appears in visitor's tab.

[1]: https://github.com/odoo/odoo/commit/3ae11c87e8a395219229416c2777bcdcdacd08ac



task-2922959

closes odoo/odoo#100173

Signed-off-by: Romain Derie (rde) <rde@odoo.com>

addons/bus/__manifest__.py

@@ -19,6 +19,7 @@
         'web.assets_frontend': [
             'bus/static/src/*.js',
             'bus/static/src/services/**/*.js',
+            ('remove', 'bus/static/src/services/assets_watchdog_service.js'),
             'bus/static/src/workers/websocket_worker.js',
             'bus/static/src/workers/websocket_worker_utils.js',
         ],