Fix code example in QueryInterface::condition()

The following docblock at [QueryInterface::condition](https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Entity%21...) is incorrect:

$entity_ids = \Drupal::entityQuery($entity_type)
    ->condition('greetings', 'merhaba', '=', 'tr')
    ->condition('greetings.value', 'siema', '=', 'pl')
    ->execute();
$entity_ids = $query->execute();

The last line is not needed.