Github integration produces invalid markup for softbreaks

[aonnikov]

See UBERF-7376

There was a bullet list with the following structure produced by github integration:

• doc
  • bulletList
  • listItem
    • paragraph
  • listItem
    • paragraph
    • text
    • paragraph
    • image

when I’m trying to replicate the same in the editor, the last item looks like:

• listItem
  • paragraph
  • text
  • hardbreak
  • image

_{Huly®: UBERF-7381}