Add stateless rightWitness computation

[shuse2]

Description

Add function in lisk-tree as below.
the size and appendPath are the size and appendPath before including the values, and the values are the data for right witness

calculateRightWitness = (
	size: number,
	appendPath: Buffer[],
	values: Buffer[],
): Buffer[];

Motivation

Add stateless right witness computation using appendpath/size and the appending values in order to compute the rightwitness easily while creating the CCM