No, the other one
According to the Belfast Telegraph, Ridley Scott's (Prometheus) mysterious "digital feature" has begun filming. It's set to come out later this year. Scott is attached as executive producer, and Battlestar Galactica director Sergio Mimica-Gezzan is directing.
This is a different project than the Steven Spielberg Halo TV series that Microsoft announced last year.
Ridley Scott's Halo digital feature being shot in Belfast's Titanic Quarter [Belfast Telegraph]