Updated web module tests so they work reliably in newer Chrome and Firefox versions. The changes remove fragile image comparisons and make date sorting consistent, reducing false test failures without changing user-facing behavior.

This fix updates appointment and rental website snippets to use Odoo's newer asset loading approach. It helps keep these website features compatible with the platform and reduces the risk of display or behavior issues after updates.

See https://github.com/odoo/odoo/pull/104836

task-2963840