fix: incorrect amount based on payment days in timesheet salary slip

[ruchamahabal]

Problem

1. Create a Salary Structure with "Salary Slip Based on Timesheet" enabled.
2. Add other components to the structure with "Depends on Payment Days" checked.
3. Mark the Employee absent for a few days.
4. Create a Salary Slip. If the Payment Days are less than the Total Days, the system won't calculate amounts based on Payment Days for other components.

Fix

It skips Payment Days calculation for all components when Salary Slip is based on Timesheet. It should only skip payment days calculation for the Timesheet Component and correctly calculate for others.

[codecov]

Codecov Report

Merging #28845 (7ff0aa7) into develop (7fd0610) will increase coverage by 7.35%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop   #28845      +/-   ##
===========================================
+ Coverage    47.28%   54.63%   +7.35%     
===========================================
  Files         1125     1125              
  Lines        66983    66984       +1     
===========================================
+ Hits         31674    36600    +4926     
+ Misses       35309    30384    -4925     

Impacted Files	Coverage Δ
erpnext/payroll/doctype/salary_slip/salary_slip.py	83.73% <100.00%> (+0.02%)	⬆️
erpnext/education/doctype/student/student.py	73.68% <0.00%> (-3.16%)	⬇️
...ion/doctype/course_enrollment/course_enrollment.py	44.00% <0.00%> (-2.00%)	⬇️
...ype/account/chart_of_accounts/chart_of_accounts.py	77.24% <0.00%> (-0.69%)	⬇️
erpnext/controllers/buying_controller.py	86.84% <0.00%> (+0.23%)	⬆️
erpnext/projects/doctype/project/project.py	54.09% <0.00%> (+0.35%)	⬆️
erpnext/accounts/doctype/account/account.py	71.76% <0.00%> (+0.39%)	⬆️
erpnext/controllers/item_variant.py	70.76% <0.00%> (+0.51%)	⬆️
...stock/doctype/purchase_receipt/purchase_receipt.py	90.90% <0.00%> (+0.53%)	⬆️
...rpnext/accounts/doctype/pos_invoice/pos_invoice.py	70.47% <0.00%> (+0.55%)	⬆️
... and 169 more

[ruchamahabal]

Unrelated test case failing. Will fix separately

[ruchamahabal]

@Mergifyio backport version-13-hotfix version-12-hotfix

[mergify]

backport version-13-hotfix version-12-hotfix

✅ Backports have been created

• #28874 fix: incorrect amount based on payment days in timesheet salary slip (backport #28845) has been created for branch version-13-hotfix
• #28875 fix: incorrect amount based on payment days in timesheet salary slip (backport #28845) has been created for branch version-12-hotfix