fix: Tax breakup based on items, missing GST fields (backport #27524)

[mergify]

This is an automatic backport of pull request #27524 done by Mergify.
Cherry-pick of d49346a has failed:

On branch mergify/bp/version-13-pre-release/pr-27524
Your branch is up to date with 'origin/version-13-pre-release'.

You are currently cherry-picking commit d49346ac45.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   erpnext/accounts/doctype/pos_invoice/pos_invoice.py
	modified:   erpnext/accounts/doctype/sales_invoice/test_sales_invoice.py
	new file:   erpnext/patches/v13_0/gst_fields_for_pos_invoice.py
	modified:   erpnext/regional/india/utils.py

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   erpnext/patches.txt
	both modified:   erpnext/regional/india/setup.py

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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