BOM jobsets save the BOM presets multiple times into the project directory

Description

If the user runs a jobset which creates a BOM then kicad will save the existing BOM presets multiple times in the project directory (in the project file *.kicad_pro).

I have the priority set to medium because it really clutters the project file.

Steps to reproduce

  1. open example project: bom_multiple_presets2.zip
  2. look for existing BOM presets: schematic editor-->schematic setup-->General-->BOM presets: 3x preset
  3. switch to kicad main manager, open available jobset panel, run the jobset (includes only BOM output) multiple times
  4. after succesfully getting the BOM: switch again to the schematic editor and examine the again the existing BOM presets: schematic editor-->schematic setup-->General-->BOM presets: now we have many times the same presets
  5. close kicad (all settings are saved)
  6. open bom_multiple_presets2.kicad_pro with a ASCII text editor, you will really find multiple entries for the same presets (CSV/TSV)

saved_multiple_presets2

KiCad Version

Application: KiCad x64 on x64

Version: 9.0.0-rc3-1-g66cbc8127b, release build

Libraries:
	wxWidgets 3.2.6
	FreeType 2.13.3
	HarfBuzz 10.2.0
	FontConfig 2.15.0

Platform: Windows 10 (build 19045), 64-bit edition, 64 bit, Little endian, wxMSW
OpenGL: Intel, Intel(R) HD Graphics 4000, 4.0.0 - Build 10.18.10.5161

	wxWidgets: 3.2.6 (wchar_t,wx containers)
	Boost: 1.86.0
	OCC: 7.8.1
	Curl: 8.11.1-DEV
	ngspice: 44
	Compiler: Visual C++ 1942 without C++ ABI
	KICAD_IPC_API=ON

Locale: 
	Lang: en_GB
	Enc: UTF-8
	Num: 1,234.5
	Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)