dynamic_entity_reference 8.x-1.6

This is release is compatible with Drupal core 8.6.0.

Changes since 8.x-1.5:

• #2970836 by jibran, das-peter, Berdir: Argument 3 passed to Drupal\hal\Normalizer\EntityReferenceItemNormalizer::__construct() must implement interface Drupal\Core\Entity\EntityTypeManagerInterface or be null
• #2993655 by jibran: Convert JavascriptTestBase Tests to use DrupalSelenium2Driver
• #2849669 by jibran: Fix \Drupal\Component\Utility\Unicode() because of the Symfony mbstring polyfill
• #2895532 by jibran: @DataType=map cannot be normalized, affects @FieldType=link, @FieldType=map