Extract Public Key

Extract Public Key Retrieves the public key associated with a given private key. This function requires inputs as follows:

• Private Key (PEM) 1 : Byte array, private key bytes encoded as PEM.
• Password 2 : UTF-8 String, pass-phrase used to decrypt the private key (should stay empty if the key is not encrypted).

If successful, returns a byte array containing the associated public key 3.