Fixes #302 ☕️

LocalDatastoreHelper works on top of gcloud utility and relies on the user input in this specific scenario, As LocalDatastoreHelper programmatically controls the gcloud command, we are using --quiet flag to disable all the prompts for user inputs and use default values instead.

Steps to reproduce (from #302 itself)

• Remove beta component gcloud components remove beta
• Run the following code

public class DatastoreGithubIssue302 {
  public static void main(String[] args) throws Exception {
    LocalDatastoreHelper emulator = LocalDatastoreHelper.create();
    emulator.start();

    System.out.println("Started!"); // will never be printed
  }
}

Also, refactoring the code a bit by configuring the gcloud datastore emulator command in a separate utility.