[REF] sales_team: Clean _get_default_team

This commit changes the method _get_default_team_id so that it removes
the xmlid reference to the default team. Instead, we will now use
the team sequence (with default team's sequence being set as 1)
and falling back to the next team with the highest sequence if the
default team got deleted.

Therefore, teams will now be ordered by sequence instead of name,
allowing the users to reorder their teams as they see fit

This commit also removes useless sudo when searching teams

Task: #1962182
PR: #32372

wip

Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>