fix: groups for current accounts in German CoAs

[barredterra]

• Rename "Trade receivables" to "Trade receivables with current account" and convert to group. Add single account "Trade receivables without current account".
• Rename "Trade payables" to "Trade payables with current account" and convert to group. Add single account "Trade payables without current account".
• Remove redundant "Debtors" and "Creditors" groups

This only affects new sites/companies and makes sure they start off with a more correct CoA.

[codecov]

Codecov Report

Merging #38803 (259f313) into develop (5a83a16) will increase coverage by 0.02%.
Report is 55 commits behind head on develop.
The diff coverage is 90.90%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #38803      +/-   ##
===========================================
+ Coverage    60.08%   60.10%   +0.02%     
===========================================
  Files          759      759              
  Lines        69556    69648      +92     
===========================================
+ Hits         41790    41861      +71     
- Misses       27766    27787      +21     

Files	Coverage Δ
...unts/report/purchase_register/purchase_register.py	86.33% <ø> (ø)
erpnext/accounts/utils.py	73.82% <ø> (+0.03%)	⬆️
erpnext/controllers/accounts_controller.py	85.14% <100.00%> (+0.04%)	⬆️
...tax_withholding_details/tax_withholding_details.py	80.12% <66.66%> (ø)

... and 17 files with indirect coverage changes