This. Found the high spot and gave it a tweak.
Little word of advice........don't do that.
One, it's just wrong, two, i've never heard of a warped rear disc, EVER, and three, don't do that ever again.....please.
You aren't 'fixing' anything by bending a disc. If it needs changing, then simply change it.
I doubt very very much that it's warped anyway, just give your caliper a good clean up and use Red Rubber grease on the outer pistons, do it once or twice a year and it will not misbehave.