PdfPkcs7RsaSigner constructor Null safety

const PdfPkcs7RsaSigner(
  1. {required Uint8List privateKey,
  2. required HashAlgorithm digest,
  3. List<X509> chain = const <X509>[],
  4. required X509 issuer,
  5. TimestampSignCallback? onTimestampSign}
)

Create a Pkcs7 RSA signer