Content Blocks: in the document editor, red invalidation markings do not move together with an invalid block

If a content block appears invalid (with a required field and after clicking save & close), and you move that block to another position in the list, the red markers do not move with that invalid block.

For compounds this was fixed with CMS-10772. The same fix should be applied to Content Blocks. To be applied to org.onehippo.forge.contentblocks.ContentBlocksFieldPlugin.