Backport of 747ac40b

Currently the test in stock_account/tests/test_stockvaluationlayer.py for Anglo-Saxon accounting is slightly wrong as it uses a company that can change depending on which l10n is installed (mainly coming from the company's country_id and account_fiscalcountry_id). This means that the test might be running with different settings from one time to another (= non-deterministic) and fail in some circumstances.

This commit fixes this issue by making this test an AccountTestInvoicingCommon test instead. This allows for the use of a test company, always the same. Of course, a few items have to be re-created since they can't be inherited anymore.

closes odoo/odoo#105205

Signed-off-by: Quentin De Paoli <qdp@odoo.com>