Adjust Y axis tick test.
Adjust Y axis tick test.

Travis fails the test due to off-by-1.

jacqt/plottable,danmane/plottable,RobertoMalatesta/plottable,NextTuesday/plottable,alyssaq/plottable,palantir/plottable,softwords/plottable,palantir/plottable,RobertoMalatesta/plottable,NextTuesday/plottable,alyssaq/plottable,gdseller/plottable,RobertoMalatesta/plottable,palantir/plottable,danmane/plottable,gdseller/plottable,danmane/plottable,jacqt/plottable,onaio/plottable,iobeam/plottable,NextTuesday/plottable,iobeam/plottable,softwords/plottable,onaio/plottable,jacqt/plottable,softwords/plottable,alyssaq/plottable,iobeam/plottable,palantir/plottable,gdseller/plottable,onaio/plottable