Fixing warning in command SubtractAssetQuantity, removing unnecessarily includes, small documentation change #3149

Job	Run time
pr_comment_reaction_rocket	0s
Pull requests from forks should use other workflow	2s
Check if github workflows were properly made from sources	25s
generate_matrixes	9s
prepare-macos-env	4s
Docker-iroha-builder	3m 48s
prepare-windows-env	4s
build-W	0s
build-M (macos clang Debug normal)	1h 12m 39s
build-M (macos clang Release normal)	1h 27m 14s
build-M (macos gcc-10 Debug normal)	1h 11m 36s
build-M (macos gcc-10 Release normal)	1h 29m 49s
build-UR (ubuntu gcc-9 Release burrow)	31m 49s
build-UR (ubuntu gcc-9 Release normal)	50m 41s
build-UD (ubuntu clang-10 Debug burrow)	28m 2s
build-UR (ubuntu gcc-9 Release ursa)	52m 23s
build-UD (ubuntu clang-10 Debug normal)	50m 57s
build-UR (ubuntu gcc-10 Release burrow)	29m 34s
build-UD (ubuntu clang-10 Debug ursa)	53m 12s
build-UR (ubuntu gcc-10 Release normal)	48m 34s
build-UD (ubuntu gcc-9 Debug burrow)	30m 46s
build-UR (ubuntu gcc-10 Release ursa)	49m 27s
build-UD (ubuntu gcc-9 Debug normal)	59m 53s
build-UD (ubuntu gcc-9 Debug ursa)	1h 1m 29s
build-UD (ubuntu gcc-10 Debug burrow)	29m 27s
build-UD (ubuntu gcc-10 Debug normal)	57m 39s
build-UD (ubuntu gcc-10 Debug ursa)	57m 50s
docker-R	0s
docker-D	0s
	16h 57m 33s

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