deleteUser method
This is used by an authenticated user to delete him/herself
Implementation
Future<bool> deleteUser() async {
if (_signInUserSession == null || !_signInUserSession!.isValid()) {
throw Exception('User is not authenticated');
}
final paramsReq = {
'AccessToken': _signInUserSession!.getAccessToken().getJwtToken(),
};
await client!.request('DeleteUser', paramsReq);
await clearCachedTokens();
return true;
}