How to handle the ground wire with my Ikea ceiling light?

Any tape for connection of the wire is not accepted by CEC. You can Use the marrettes or approved connector that is capable for the Gauge of wire using (Mainly 14 guage in house for 15 amp). You need to ask a pro for this installation for making sure everything would be according Canadian electrical code and your house be insured safely.

Under the Ontario Electrical Code (OEC), you should never tape off or cap a building ground wire if one is present in the supply box. Even though the IKEA pendant fixture has a plastic housing and lacks a grounding terminal, proper treatment of the supply ground is essential for circuit continuity. ​Key ESA & Code-Compliant Steps: ​Maintain Circuit Ground Continuity: The green-and-yellow ground wire coming from your ceiling box is part of the branch circuit's continuous equipment grounding system. It must remain electrically active to protect downstream devices or metal junction components. ​Never Use Tape: Electrical tape is never an acceptable method for terminating or securing a ground wire. ​Proper Termination: Secure the ceiling's bare or green-and-yellow ground wire using an approved wire connector (such as a wire nut) or fold it safely back into the junction box. If the ceiling box is metal, the ground wire must be bonded directly to the box using a green grounding screw first, with a pigtail if necessary. ​A licensed electrician can ensure your ceiling box is correctly grounded and that your fixture is installed safely to code.