requestAndConfirmAirdrop method
      
Future<TransactionSignature> 
requestAndConfirmAirdrop(
    
- Pubkey pubkey,
- u64 lamports, {
- CommitmentConfig? config,
Requests an airdrop of lamports to pubkey and wait for transaction confirmation.
Returns the transaction signature as a base-58 encoded string.
Implementation
Future<TransactionSignature> requestAndConfirmAirdrop(
  final Pubkey pubkey,
  final u64 lamports, {
  final CommitmentConfig? config,
}) async {
  final TransactionSignature signature = await requestAirdrop(
    pubkey,
    lamports,
    config: config,
  );
  final SignatureNotification notification = await confirmTransaction(
    signature,
    config: config,
  );
  return notification.err != null
      ? Future.error(notification.err)
      : Future.value(signature);
}