Add a new subtype_id for 'RFQ Sent' state. This removes
the need to join on mail.tracking.value when computing
'all_sent_rfqs'. Since mail.tracking.value is usually
a big table, removing this join leads to a substantial
speedup when loading the purchase.order dashboard on big
databases.
closesodoo/odoo#96921
Signed-off-by: Arnold Moyaux (arm) <arm@odoo.com>
