Remove unused AxisConfig interface
Remove unused AxisConfig interface

OurWorldInData/owid-grapher,owid/owid-grapher,owid/owid-grapher,owid/owid-grapher,OurWorldInData/owid-grapher,OurWorldInData/owid-grapher,owid/owid-grapher,OurWorldInData/owid-grapher,OurWorldInData/owid-grapher,owid/owid-grapher