Yep, it's the new background from the adventure. The adventure also has BG-specific versions of a bunch of the PHB backgrounds:
"Some backgrounds have at least one new variant feature that ties the background to a group in Baldur’s Gate, provided to give characters an additional connection to the city. Characters may choose to replace the standard feature of their background with one of these variant features. Each background also includes a bonus feature that marks a character as a native of Baldur’s Gate who’s familiar with the city — both its streets and its scars. These additional featu…