[FIX] sale_timesheet: UOM

Revert commits da2140b726, e65c8826ef and 06cd145a79. They
introduce an incorrect UOM.

The original issue was an `AccessError` due to the fact that the
employee chosen was not in the same company than the user. Therefore,
instead of changing the logic of the UOM selection, we make sure to
select the employee in the appropriate company first, then fall back on
any company then.

opw-1888299

addons/sale_timesheet/models/account.py

@@ -38,10 +38,12 @@ class AccountAnalyticLine(models.Model):
                 return {}
             unit_amount = values.get('unit_amount', 0.0) or self.unit_amount
             user_id = values.get('user_id') or self.user_id.id or self._default_user()
-            emp = self.env['hr.employee'].search([('user_id', '=', user_id)], limit=1)
-            account = values.get('account_id') and self.env['account.analytic.account'].browse([values['account_id']]) or self.account_id or emp.account_id
+            user = self.env['res.users'].browse([user_id])
+            emp = self.env['hr.employee'].search([('user_id', '=', user_id), ('company_id', '=', user.company_id.id)], limit=1)
+            if not emp:
+                emp = self.env['hr.employee'].search([('user_id', '=', user_id)], limit=1).sudo()
             cost = emp and emp.timesheet_cost or 0.0
-            uom = account.sudo().company_id.project_time_mode_id
+            uom = (emp or user).company_id.project_time_mode_id
             # Nominal employee cost = 1 * company project UoM (project_time_mode_id)
             return {
                 'amount': -unit_amount * cost,