I first thought Acacia subulata, but the seed pods are wide and constricted. The only A. subulata I knew was on Isaacs Ridge Acacia subulata (Awl-leaved Wattle) until @NedJohnston reported one at the ANU. Most ALA records for the ACT are from ANBG or some planting in O'Connor. There is now new growth at Isaacs Ridge but no seed pods yet.
I was going by the description and photos in https://apps.lucidcentral.org/wattle/text/entities/acacia_subulata.htm. Maybe the pods look different when there are only a few seeds.