feat: minor enhancements in Employee Promotion

[ruchamahabal]

Before

• Employee Promotion has a child table for adding all the employee properties that should be updated with the promotion like department, designation, etc. These fields were hardcoded so if users want to update any custom fields or want to track additional fields with their old and new values in the promotion, this wasn't possible.
• No fields to track CTC in Employee as well as Employee Promotion.

promotion-before.mp4

After

• Removed hardcoded fields (some don't even exist in employee master anymore) that can be tracked in Promotion. Changed field type to Autocomplete for easier searching.
• Fixed: Property addition was not working for select fields
• Added CTC field in Employee master
• Added Current CTC and Revised CTC in Employee Promotion. Revised CTC gets updated in Employee master on promotion submission.

employee-promotion-after.mp4

Also removing Employee Transfer Property doctype which does nothing:

Docs:

• Employee Promotion: https://docs.erpnext.com/docs/v14/user/manual/en/human-resources/employee_promotion/edit?wiki_page_patch=09a612deb1
• Employee master: https://docs.erpnext.com/docs/v14/user/manual/en/human-resources/employee/edit?wiki_page_patch=58709b16c8

P.S.: This also updates Employee Transfer because it uses the same property updater.

[codecov]

Codecov Report

Merging #30780 (8e5327a) into develop (e088e65) will increase coverage by 0.18%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop   #30780      +/-   ##
===========================================
+ Coverage    61.46%   61.65%   +0.18%     
===========================================
  Files         1080     1079       -1     
  Lines        69537    69542       +5     
===========================================
+ Hits         42741    42873     +132     
+ Misses       26796    26669     -127     

Impacted Files	Coverage Δ
erpnext/hr/utils.py	77.73% <ø> (+1.26%)	⬆️
...r/doctype/employee_promotion/employee_promotion.py	100.00% <100.00%> (+15.78%)	⬆️
.../report/delayed_item_report/delayed_item_report.py	60.78% <0.00%> (-35.30%)	⬇️
...e_sales_analytics/supplier_wise_sales_analytics.py	81.96% <0.00%> (-4.92%)	⬇️
...ctype/woocommerce_settings/woocommerce_settings.py	80.76% <0.00%> (-3.85%)	⬇️
...eorder_level/itemwise_recommended_reorder_level.py	90.74% <0.00%> (-1.86%)	⬇️
erpnext/portal/utils.py	28.98% <0.00%> (-1.45%)	⬇️
erpnext/support/doctype/issue/issue.py	64.25% <0.00%> (-0.97%)	⬇️
erpnext/controllers/sales_and_purchase_return.py	85.07% <0.00%> (-0.75%)	⬇️
erpnext/stock/stock_ledger.py	87.62% <0.00%> (-0.17%)	⬇️
... and 22 more