code: public static AuthToken basic( String username, String password, String realm )
      {
          Objects.requireNonNull( username, "Username can't be null" );
          Objects.requireNonNull( password, "Password can't be null" );
  
          Map<String,Value> map = newHashMapWithSize( 4 );
          map.put( SCHEME_KEY, value( "basic" ) );
          map.put( PRINCIPAL_KEY, value( username ) );
          map.put( CREDENTIALS_KEY, value( password ) );
          if ( realm != null )
          {
              map.put( REALM_KEY, value( realm ) );
          }
          return new InternalAuthToken( map );
      }
docs: The basic authentication scheme, using a username and a password.
  @param username this is the "principal", identifying who this token represents
  @param password this is the "credential", proving the identity of the user
  @param realm this is the "realm", specifies the authentication provider
  @return an authentication token that can be used to connect to Neo4j
  @see GraphDatabase#driver(String, AuthToken)
  @throws NullPointerException when either username or password is {@code null}