Fix typo in link to English Wikipedia page for Iris data set
The :meth:`pygmt.Figure.plot3d` method can be used to plot symbols in 3D.
In the example below, we show how the
-`Iris flower dataset <https://en.wikipedia.org/wiki/Iris_flower_data_set/>`__
+`Iris flower dataset <https://en.wikipedia.org/wiki/Iris_flower_data_set>`__
can be visualized using a perspective 3-dimensional plot. The ``region``
argument has to include the :math:`x`, :math:`y`, :math:`z` axis limits in the
form of (xmin, xmax, ymin, ymax, zmin, zmax), which can be done automatically
