generatePassword method
Implementation
String generatePassword(
{required String mPassKey, required String mShortCode, required String actualTimeStamp}) {
///Adds up the paybill no., the timestamp & passkey to generate a base64
///code to be added to the request body as unique password to auth
///the request in question.
String readyPass = mShortCode + mPassKey + actualTimeStamp;
var bytes = utf8.encode(readyPass);
return base64.encode(bytes);
}