Purpose
=======
The existing timesheets linked to a time off are unlinked once the
time off is refused (which is the only action on the interface for
validated time off).
But nothing prevents to set in a python code a time off directly
in draft to validate it afterward.
In that case, the timesheet is duplicated and is impossible to unlink
as this is forbidden for timesheets linked to a time off.
Specification
=============
Make sure before creating timesheets linked to a time off that there
is not remaining linked timesheets.
On the other hand, modify the method to generate the timesheets in batch.
X-original-commit: 46a3394b960ba344d49a4e99ae5a6a7d7392dbf6
Part-of: odoo/odoo#84269
Yannick Tivisse
959a05d00c