Certs on plug in lighting

As the title, I’m in the middle of a big lighting upgrade project and trying to keep on top of my testing as I go. Some of the lights I’ve replaced are high bays, fed from a bus bar. I’ve removed the plug, rewired it with the new light, and plugged it back in.

Am I being dense (quite possible) or surely there’s no cert required for that as I haven’t “altered a circuit” if it’s plugged in and not fixed.

Thoughts/comments appreciated