3rd party companies make these[0]. It's a little plug into the USB-C port, then a break away cable.
My only complaint about the usb-c is that they're on the same side. I've gotten used to flipping back and forth on my mbp for plugging it in. (different setup at home and work)
[0]https://www.amazon.com/Griffin-BreakSafe-Magnetic-Breakaway-...