fix: don't depreciate assets with no schedule on scrapping

[anandbaburajan]

When an asset with no depreciation schedules is scrapped, it's value is unnecessarily getting set to it's original value -- which shouldn't have happened because that asset could have manual depreciation entries created for them. Now the asset's value won't be changed in this case.

[codecov]

Codecov Report

Merging #38276 (fb40504) into develop (74f9e34) will decrease coverage by 0.01%.
Report is 15 commits behind head on develop.
The diff coverage is 90.32%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #38276      +/-   ##
===========================================
- Coverage    67.27%   67.26%   -0.01%     
===========================================
  Files          757      757              
  Lines        60515    60519       +4     
===========================================
+ Hits         40709    40711       +2     
- Misses       19806    19808       +2     

Files	Coverage Δ
...ounts/doctype/purchase_invoice/purchase_invoice.py	84.29% <100.00%> (ø)
...post_accounting_ledger/repost_accounting_ledger.py	94.69% <100.00%> (ø)
...xt/accounts/doctype/sales_invoice/sales_invoice.py	83.83% <100.00%> (ø)
erpnext/assets/doctype/asset/asset.py	80.44% <100.00%> (ø)
erpnext/controllers/buying_controller.py	83.94% <ø> (ø)
...stock/doctype/purchase_receipt/purchase_receipt.py	91.29% <100.00%> (ø)
...serial_and_batch_bundle/serial_and_batch_bundle.py	73.15% <100.00%> (ø)
erpnext/projects/doctype/timesheet/timesheet.py	78.34% <66.66%> (ø)
erpnext/assets/doctype/asset/depreciation.py	83.28% <50.00%> (-0.41%)	⬇️