If your fig is a grafted variety and the growth is coming from below the graft you will want to prune this growth off as it is likely a different variety of fig than the top of the plant. This is a common issue with figs where growth from below the graft dominates the plant and people are disappointed the figs they harvest are of a different variety. Growth from below the graft is a fig variety that has a sturdy root, but not best for eating. This is the same for most grafted plants including roses and fruit trees.
You can "tip root" any suckers that grow out of your mother plant's root ball any time, or if you want to cut them off, do so right away, before it gets too late in the season. These articles may help you:
https://www.gardeningknowhow.com/edible/fruits/figs/fig-propagation.htm
https://www.gardeningknowhow.com/edible/fruits/figs/growing-figs-in-pots.htm
