Remove stray simple

Co-authored-by: hannah <[email protected]>

Author: CouldNot

galleries/plot_types/basic/stairs.py

@@ -3,7 +3,7 @@
 stairs(values)
 ==============
 
-See `~matplotlib.axes.Axes.stairs` when plotting :math:`y$` between
+See `~matplotlib.axes.Axes.stairs` when plotting :math:`y` between
 :math:`(x_i, x_{i+1})`. For plotting :math:`y` at :math:`x`, see
 `~matplotlib.axes.Axes.step`.