fun computeNonce(privacySalt: PrivacySalt, groupIndex: Int, internalIndex: Int): SHA256
Method to compute a nonce based on privacySalt, component group index and component internal index. SHA256d (double SHA256) is used to prevent length extension attacks.
privacySalt - a PrivacySalt.
groupIndex - the fixed index (ordinal) of this component group.
internalIndex - the internal index of this object in its corresponding components list.
SHA256(SHA256(privacySalt || groupIndex || internalIndex))