encrypt method
Implementation
String encrypt(Map<String, String> data) {
final jsonData = json.encode(data);
final jsonBytes = utf8.encode(jsonData);
final encryptor = OAEPEncoding(RSAEngine())
..init(true, PublicKeyParameter<RSAPublicKey>(publicKey));
final encrypted = encryptor.process(jsonBytes);
return base64Encode(encrypted);
}