create Private Key
Creates a private key using the provided properties.
Return
A PrivateKey object representing the created private key.
Parameters
properties
A map containing the properties of the private key. The supported properties are: - "type": The type of the private key. Use KeyTypes.EC for elliptic curve keys. - "seed": The seed used for key generation. Must be a byte array. - "curve": The key curve. Use Curve.SECP256K1 for secp256k1 curve.