Fixing warning in command SubtractAssetQuantity, removing unnecessarily includes, small documentation change #3163

Job	Run time
Pull requests from forks should use other workflow	3s
pr_comment_reaction_rocket	0s
Check if github workflows were properly made from sources	13s
generate_matrixes	4s
Docker-iroha-builder	3m 38s
prepare-windows-env	4s
prepare-macos-env	3s
build-W	0s
build-M (macos clang Debug normal)	1h 16m 34s
build-UR (ubuntu gcc-10 Release normal)	48m 55s
build-UD (ubuntu gcc-10 Debug normal)	56m 39s
docker-R	0s
docker-D	0s
	3h 6m 13s

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