Remove unsued variable

Author: SamuMazzi

implot_demo.cpp

@@ -2131,7 +2131,6 @@ void Demo_ColormapWidgets() {
 void Demo_PlotLimitsChanging() {
     unsigned int lin[10] = {8,8,9,7,8,8,8,9,7,8};
     unsigned int bar[10] = {1,2,5,3,4,1,2,5,3,4};
-    unsigned int dot[10] = {7,6,6,7,8,5,6,5,8,7};
 
     if (ImPlot::BeginPlot("##LimitsChanging")) {
         ImPlot::SetupAxes( "x-axis", "y-axis");