How to hide the label of a entity referenced image field
Starting in Lightning 2.2.4, you can manage the label in the Media Entity's Manage Display tab.

See this issue for more information: https://www.drupal.org/node/2922289


  Include patch to omit media name
  
  Until this is fixed in core, it would be good to have the patch from [#2912298: Make media name available on manage display] included so that media name can be removed from display. This is especially crucial for lightning upgrades with existing media embeds.