Video Embed Field module migration

[trubach]

The Video Embed Field (https://www.drupal.org/project/video_embed_field) module is installed via the ILFW core module. This article describes how to migrate video embed fields to using core's Drupal Media system:

https://blog.horizontaldigital.com/how-migrate-video-embed-wysiwyg-drupal-core-media

We should work towards

1. Migrate any content out of the video embed field and into Drupal's core media
2. Disable video_embed_field module and remove it from the WYSIWYG editor toolbar
3. Removing the module from ILFW core

Steps 1 & 2 can happen in a single release, but step 3 should happen in a later release, so that the module isn't removed by composer before the drupal update hook can disable/migrate it.