Remove duplicate "Library reaction" declaration for Multikinetics in chemkin commentary.
Remove duplicate "Library reaction" declaration for Multikinetics in chemkin commentary.

comocheng/RMG-Py,nyee/RMG-Py,enochd/RMG-Py,enochd/RMG-Py,pierrelb/RMG-Py,comocheng/RMG-Py,chatelak/RMG-Py,nyee/RMG-Py,pierrelb/RMG-Py,nickvandewiele/RMG-Py,nickvandewiele/RMG-Py,chatelak/RMG-Py