[FIX] web: custom filter on selection field shows DB value

before this commit: custom filter on selection field shows database value while
it should display user freidnly value.

after this commit: custom filter on selection field will display UI value of
selection attribute instead of database value.

task-2363112

closes odoo/odoo#60161

Signed-off-by: FrancoisGe <fge@odoo.com>