## [FIX] account_disallowed_expenses_fleet: query is mixing apple and pear

The aim of this commit is to make the report behaves correctly when
facing a DB with a lot of vehicles and a lot of accounts by making the
query `group by` and `order by` more robust.

Context:
- 1 account and 1 vehicle share the same number for the id
- the account is tagged with disallowed expense tag
- 1 `account.move.line` without vehicle in that account
- 1 `account.move.line` with a vehicle (with a dna rate) in the same
  account

Before the commit:
- The computation is giving wrong result in the report: 2 `account.move.line`
  were aggregated together under the hierarchy of the account without vehicle
  and the vehicle doesn't appear in the report at all.
  cause: the `CASE WHEN` could return, for example `92` as a `vehicle_id` and
  then `92` as an `account_id` and thus have them regrouped together.

- 2 lines of the report were sharing the same "line_id" (the id given by
  report framework id, see method `_build_line_id`) which are used in a
  t-key property in an OWL loop resulting in a crash for the front-end.

After the commit:
- The 2 lines are aggregated seperatly: The line without `vehicle_id` is under
  the hierarchy of the account and the line with `vehicle_id` is under the
  hierachy of the concerned vehicle.
- The line doesn't share any line_id anymore

task-id: None (issue discovered in our own prod)

## [IMP] account_reports: ensure line_id is uniq in tests

Moved to https://github.com/odoo/enterprise/pull/66216

Forward-Port-Of: odoo/enterprise#64166