fix: Gross Profit Report with Correct Totals and Gross Margin (backport #45548)

[mergify]

Support ticket: Support Ticket - 30225

• closes : Gross Profit Report error #35942

Before :
The add_total_row option was checked, causing the subtotals to combine, which resulted in an incorrect Selling Amount, Buying Amount, Gross Profit, Gross Profit Percentage.

After :
The total Selling Amount and Buying Amount are now calculated correctly.
The total Gross Profit and Gross Profit Percentage is calculated using a formula.
The add_total_row option was disabled using a patch.

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This is an automatic backport of pull request #45548 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of aaf720a has failed:

On branch mergify/bp/version-14-hotfix/pr-45548
Your branch is up to date with 'origin/version-14-hotfix'.

You are currently cherry-picking commit aaf720ab61.
  (fix conflicts and run "git cherry-pick --continue")
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Changes to be committed:
	modified:   erpnext/accounts/report/gross_profit/gross_profit.json
	modified:   erpnext/accounts/report/gross_profit/gross_profit.py
	new file:   erpnext/patches/v14_0/disable_add_row_in_gross_profit.py

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   erpnext/accounts/report/gross_profit/test_gross_profit.py
	both modified:   erpnext/patches.txt

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