[FIX] mrp: force kit to be consumable product

Kits must be consumable products, they might never be in stock.
Setting kits as storable products can create some issues if the user
creates some reordering rules.

Because kits might never be in stock, it's impossible to fullfil the
quantity of a reordering rule: asking a mini/maxi quantity on a kit
makes no sense.

Odoo will continuously propose to order more to reach the quantity
necessary for the kit, but will never reach the asked qty, as it's a
kit, not a manufactured product.

OPW-2448878

closes odoo/odoo#65339

Signed-off-by: Steve Van Essche <svs-odoo@users.noreply.github.com>