Odoo removes an older analytic filter from accounting and Spanish tax reports in favor of a newer grouping-based approach. This should make analytic reporting more consistent because it takes analytic distribution into account while reducing duplicate filtering options.

Removing `filter_analytic`, as `filter_analytic_groupby` does the job
better and considers the analytic distribution.

Enteprise PR: https://github.com/odoo/enterprise/pull/92598

task-4819486

The checkout discount subtotal option had already stopped being configurable, so this change removes the leftover code for it. This keeps the website sales loyalty module cleaner and avoids exposing or maintaining a non-working setting.

Since 0750eb6, enabling or disabling the discount subtotal in the checkout is impossible.

This commit cleans up the code to permanently remove the feature.

See also:
- https://github.com/odoo/upgrade/pull/8550