Adhesive for metal to glass

You can use 3M Command Strips. You just need the strips themselves, and not the hook. Attach one side to the bracket and the other to the granite. When you move out, just pull down on the strip to remove.

Depending on the size, some of the strip may be visible. You may be able to trim it to size though.

Thank you for the answers guys but I actually asked the manufacturer if they have any suggestions and they came with the best solution ever :D

Apparently there is a kit available. I am not sure how one would search for this as the manufacturer sells this "glue kit" especially for this type of situations. I am not sure if this is something you can find anywhere but for reference here is the actual product.

I have not mounted it yet but once it arrives and I do the work I will try to provide more details about it.