Landing connection beta release

• Update post and put wp API headers passing content-type
• adjust update payload compatible with last wp API version

requested review from @enricostn

assigned to @DaniilDigtyar

approved this merge request

I will merge it to apply it now in the release

mentioned in commit 9875882b

merged

mentioned in merge request !195 (merged)

mentioned in merge request !209 (merged)

unassigned @DaniilDigtyar