[IMP] hr_*_attendance: leave in terms of working time not respected

As the leave is deducted from the needed time to work
in case for example Home Office which is configured as
working time (other) is handled like a real leave (absence)
which will lead to an extensive overtime instead the difference
to the work entry defining the work time.

A domain clearing out this missing link and variation
cleans up this misalignment and therefore overtime will
be computed correctly.

closes odoo/odoo#126188

Signed-off-by: Kevin Baptiste <kba@odoo.com>