Seems indeed it is gone. I had put it off myself to do it, started it day before patch but decided to wait and do it same day as patch. When I logged in next day quest was just gone. I wrote a ticket about it to get some answers.
I hate them removing content but what makes me the most angry is them not saying anything about it. Blizz, please communicate with us. Just a simple “Hey the questline will be going away in 8.3” had been enough.
Edit: I have gotten a response to the ticket and the quest is indeed removed. Since it is a “breadcrumb” quest leading up to events and those events are now happening there is no purpose of the quest according to Blizzard.
Again I hate they remove content but the thing I hate most is they do not let us know. Just a simple notice a bit before patch goes out is all that is needed.