[IMP] hr_expense, sale_expense: improve UX (back2basics)

Enterprise PR - odoo/enterprise#23980
Upgrade PR - odoo/enterprise#3206

- UI improvements/changes

- Taxes

    Before this commit, in case taxes were defined on expense,
    the tax amount was added on top of a product price.
    For example, in case product price was 100$, and tax - 15%,
    then expense.total_amount would be 115$.

    Now, tax amount is included in expense.total_amount. To accommodate
    this change, we set following domain - ('price_include', '=', True)
    on tax_ids on expense.

    For the same example, expense.total_amount would be 100$, tax amount
    would be 13.04$ and untaxed amount - 86.96$.

    But, tax amount can be set for non-zero expenses (in case expense.product_id.standard_price !=0).
    For the above example, one could set tax amount to 15$.
    As a result untaxed amount will be 85$ and total amount - 1OO$.

- Journal entry

    Previously, in case journal entry was reset to draft, canceled,
    reversed - it changed the state of the linked expense report.
    Now, actions done on accounting by accountant does not impact expense reports.

task - 2687999

closes odoo/odoo#81904

Related: odoo/upgrade#3206
Signed-off-by: Kevin Baptiste <kba@odoo.com>