Opening: I know not to underestimate humanity's ability to weaponise tools, so I want to know how they could be weaponised as they are.
Golems are non-human tools, not even slaves
Most golems in peace time never need to be weaponized, as long as they don't do tasks that require weapons. Of course, an owner could decide to weaponize his golem - say, with an axe - to kill someone, or a terrorist or mafia organisation could deploy golems as fodder.. they are not human, so they are disposable. Anything goes. When it's damaged, it can be repaired.
Deploying the golems in times of war
I suppose these "weaponized golems" could serve in a classic Clausevitz-style war, as foot soldiers. Because of their massive presence and strength, they could carry shields and other heavy armour, pushing the front line forward slowly, removing obstacles like rocks and trees, filling up trenches, building bridges. Others could be carrying supplies, or help moving wounded human soldiers.
Golems are based on magi-tech, so many human civilians and soldiers in your society should learn to apply the magic, to be able to repair them. And.. watch the enemy ! They could make good use of captured golems, stealing your magic, or apply reverse magic, to let your golem join their army. A self-destruct built into the golem, triggered on a distance by a powerful magician, could help prevent that.
Important decisions to make: what weapons of war can stupid and autonomous golems be trusted with.. are these golems always loyal at any time, or are they too stupid to discern between you and enemy targets.. and how strong is the enemy magic, is the enemy capable of turning golems against you ? weaponizing them too heavily would become risky.
You'll have to cope with protests
Because golems are human shape and commonly serve as part of human society as workers, many people will come to regard them as pets, rather than machines. Especially youth. When war breaks out and the golem is called for duty and be armed, the civilian society will loose its free work force. A lot of owners will not be prepared to send their golems out into some war and these people will try to hide their golem.