JsSignatureProvider is insecure and should not be used in production, it provides a basic example of what a
SignatureProvider is and does.
JsSignatureProvider simply takes a list of private keys as strings in its constructor and maps these private keys to their respective public keys. When
sign is called, a buffer of the
serializedTransaction is created and
ecc object is used to sign the buffer with the private key corresponding to the required public key.
What Is A Signature Provider