I feel like a lot of people here need to stop taking this information so damn personally. You didn’t know, great, that means you’re not racist. Now you do know. So just… Stop? That’s it. OP wasn’t even a dick about it.
Personally, I’m grateful when I get a heads up that certain terms are racist, so thank you OP!
I actually extended your PSA over to my Misskey. A great discussion ensued followed by this term and one other being added to the slur list. :P